Weak Security Controls and Practices Routinely Exploited for Initial Access


Best Practices to Protect Your Systems:
• Control access.
• Harden Credentials.
• Establish centralized log management.
• Use antivirus solutions.
• Employ detection tools.
• Operate services exposed on internet-accessible hosts with secure configurations.
• Keep software updated.

Cyber actors routinely exploit poor security configurations (either misconfigured or left unsecured), weak controls, and other poor cyber hygiene practices to gain initial access or as part of other tactics to compromise a victim’s system. This joint Cybersecurity Advisory identifies commonly exploited controls and practices and includes best practices to mitigate the issues. This advisory was coauthored by the cybersecurity authorities of the United States,[1],[2],[3] Canada,[4] New Zealand,[5],[6] the Netherlands,[7] and the United Kingdom.[8]

Download the PDF version of this report (pdf, 430kb).

Malicious actors commonly use the following techniques to gain initial access to victim networks.[TA0001]

Malicious cyber actors often exploit the following common weak security controls, poor configurations, and poor security practices to employ the initial access techniques.

  • Multifactor authentication (MFA) is not enforced. MFA, particularly for remote desktop access, can help prevent account takeovers. With Remote Desktop Protocol (RDP) as one of the most common infection vector for ransomware, MFA is a critical tool in mitigating malicious cyber activity. Do not exclude any user, particularly adminstrators, from an MFA requirement. 
  • Incorrectly applied privileges or permissions and errors within access control lists. These mistakes can prevent the enforcement of access control rules and could allow unauthorized users or system processes to be granted access to objects. 
  • Software is not up to date. Unpatched software may allow an attacker to exploit publicly known vulnerabilities to gain access to sensitive information, launch a denial-of-service attack, or take control of a system. This is one of the most commonly found poor security practices.
  • Use of vendor-supplied default configurations or default login usernames and passwords. Many software and hardware products come “out of the box” with overly permissive factory-default configurations intended to make the products user-friendly and reduce the troubleshooting time for customer service. However, leaving these factory default configurations enabled after installation may provide avenues for an attacker to exploit. Network devices are also often pre-configured with default administrator usernames and passwords to simplify setup. These default credentials are not secure—they may be physically labeled on the device or even readily available on the internet. Leaving these credentials unchanged creates opportunities for malicious activity, including gaining unauthorized access to information and installing malicious software. Network defenders should also be aware that the same considerations apply for extra software options, which may come with preconfigured default settings.
  • Remote services, such as a virtual private network (VPN), lack sufficient controls to prevent unauthorized access. During recent years, malicious threat actors have been observed targeting remote services. Network defenders can reduce the risk of remote service compromise by adding access control mechanisms, such as enforcing MFA, implementing a boundary firewall in front of a VPN, and leveraging intrusion detection system/intrusion prevention system sensors to detect anomalous network activity.  
  • Strong password policies are not implemented. Malicious cyber actors can use a myriad of methods to exploit weak, leaked, or compromised passwords and gain unauthorized access to a victim system. Malicious cyber actors have used this technique in various nefarious acts and prominently in attacks targeting RDP. 
  • Cloud services are unprotected. Misconfigured cloud services are common targets for cyber actors. Poor configurations can allow for sensitive data theft and even cryptojacking.
  • Open ports and misconfigured services are exposed to the internet. This is one of the most common vulnerability findings. Cyber actors use scanning tools to detect open ports and often use them as an initial attack vector. Successful compromise of a service on a host could enable malicious cyber actors to gain initial access and use other tactics and procedures to compromise exposed and vulnerable entities. RDP, Server Message Block (SMB), Telnet, and NetBIOS are high-risk services. 
  • Failure to detect or block phishing attempts. Cyber actors send emails with malicious macros—primarily in Microsoft Word documents or Excel files—to infect computer systems. Initial infection can occur in a variety of ways, such as when a user opens or clicks a malicious download link, PDF, or macro-enabled Microsoft Word document included in phishing emails. 
  • Poor endpoint detection and response. Cyber actors use obfuscated malicious scripts and PowerShell attacks to bypass endpoint security controls and launch attacks on target devices. These techniques can be difficult to detect and protect against. 

Applying the following practices can help organizations strengthen their network defenses against common exploited weak security controls and practices.

Control Access

  • Adopt a zero-trust security model that eliminates implicit trust in any one element, node, or service, and instead requires continuous verification of the operational picture via real-time information from multiple sources to determine access and other system responses.[9],[10] Zero-trust architecture enables granular privilege access management and can allow users to be assigned only the rights required to perform their assigned tasks.
  • Limit the ability of a local administrator account to log in from a remote session (e.g., deny access to this computer from the network) and prevent access via an RDP session. Additionally, use dedicated administrative workstations for privileged user sessions to help limit exposure to all the threats associated with device or user compromise. 
  • Control who has access to your data and services. Give personnel access only to the data, rights, and systems they need to perform their job. This role-based access control, also known as the principle of least priviledge, should apply to both accounts and physical access. If a malicious cyber actor gains access, access control can limit the actions malicious actors can take and can reduce the impact of misconfigurations and user errors. Network defenders should also use this role-based access control to limit the access of service, machine, and functional accounts, as well as the use of management privileges, to what is necessary. Consider the following when implementing access control models:
    • Ensure that access to data and services is specifically tailored to each user, with each employee having their own user account. 
    • Give employees access only to the resources needed to perform their tasks.
    • Change default passwords of equipment and systems upon installation or commissioning. 
    • Ensure there are processes in place for the entry, exit, and internal movement of employees. Delete unused accounts, and immediately remove access to data and systems from accounts of exiting employees who no longer require access. Deactivate service accounts, and activate them only when maintenance is performed.[11]
  • Harden conditional access policies. Review and optimize VPN and access control rules to manage how users connect to the network and cloud services.
  • Verify that all machines, including cloud-based virtual machine instances do not have open RDP ports. Place any system with an open RDP port behind a firewall and require users to use a VPN to access it through the firewall.[12]

Implement Credential Hardening

Establish Centralized Log Management

  • Ensure that each application and system generates sufficient log information. Log files play a key role in detecting attacks and dealing with incidents. By implementing robust log collection and retention, organizations are able to have sufficient information to investigate incidents and detect threat actor behavior. Consider the following when implementing log collection and retention: 
    • Determine which log files are required. These files can pertain to system logging, network logging, application logging, and cloud logging. 
    • Set up alerts where necessary. These should include notifications of suspicious login attempts based on an analysis of log files. 
    • Ensure that your systems store log files in a usable file format, and that the recorded timestamps are accurate and set to the correct time zone. 
    • Forward logs off local systems to a centralized repository or security information and event management (SIEM) tools. Robustly protect SIEM tools with strong account and architectural safeguards.
    • Make a decision regarding the retention period of log files. If you keep log files for a long time, you can refer to them to determine facts long after incidents occur. On the other hand, log files may contain privacy-sensitive information and take up storage space. Limit access to log files and store them in a separate network segment. An incident investigation will be nearly impossible if attackers have been able to modify or delete the logfiles.[13]

Employ Antivirus Programs

  • Deploy an anti-malware solution on workstations to prevent spyware, adware, and malware as part of the operating system security baseline.
  • Monitor antivirus scan results on a routine basis.

Employ Detection Tools and Search for Vulnerabilities

  • Implement endpoint and detection response tools. These tools allow a high degree of visibility into the security status of endpoints and can help effectively protect against malicious cyber actors.
  • Employ an intrusion detection system or intrusion prevention system to protect network and on-premises devices from malicious activity. Use signatures to help detect malicious network activity associated with known threat activity.
  • Conduct penetration testing to identify misconfigurations. See the Additional Resources section below for more information about CISA’s free cyber hygiene services, including remote penetration testing.
  • Conduct vulnerability scanning to detect and address application vulnerabilities. 
  • Use cloud service provider tools to detect overshared cloud storage and monitor for abnormal accesses.

Maintain Rigorous Configuration Management Programs

  • Always operate services exposed on internet-accessible hosts with secure configurations. Never enable external access without compensating controls such as boundary firewalls and segmentation from other more secure and internal hosts like domain controllers. Continuously assess the business and mission need of internet-facing services. Follow best practices for security configurations, especially blocking macros in documents from the internet.[14]

Initiate a Software and Patch Management Program 

  • Implement asset and patch management processes to keep software up to date. Identify and mitigate unsupported, end-of-life, and unpatched software and firmware by performing vulnerability scanning and patching activities. Prioritize patching known exploited vulnerabilities.

Additional Resources 

References 

[1] United States Cybersecurity and Infrastructure Security Agency 
[2] United States Federal Bureau of Investigation
[3] United States National Security Agency
[4] Canadian Centre for Cyber Security 
[5] New Zealand National Cyber Security Centre 
[6] New Zealand CERT NZ
[7] Netherlands National Cyber Security Centre
[8] United Kingdom National Cyber Security Centre 
[9] White House Executive Order on Improving the Nation’s Cybersecurity
[10] NCSC-NL Factsheet: Prepare for Zero Trust
[11] NCSC-NL Guide to Cyber Security Measures
[12] N-able Blog: Intrusion Detection System (IDS): Signature vs. Anomaly-Based
[13] NCSC-NL Guide to Cyber Security Measures
[14] National Institute of Standards and Technology SP 800-123 – Keeping Servers Secured

Contact

U.S. organizations: To report incidents and anomalous activity or to request incident response resources or technical assistance related to these threats, contact CISA at [email protected]. To report computer intrusion or cybercrime activity related to information found in this advisory, contact your local FBI field office at www.fbi.gov/contact-us/field, or the FBI’s 24/7 Cyber Watch at 855-292-3937 or by email at [email protected]. For NSA client requirements or general cybersecurity inquiries, contact [email protected]

Canadian organizations: report incidents by emailing CCCS at [email protected]

New Zealand organizations: report cyber security incidents to [email protected] or call 04 498 7654. 

The Netherlands organizations: report incidents to [email protected]

United Kingdom organizations: report a significant cyber security incident: ncsc.gov.uk/report-an-incident (monitored 24 hours) or, for urgent assistance, call 03000 200 973.

Caveats

The information you have accessed or received is being provided “as is” for informational purposes only. CISA, the FBI, NSA, CCCS, NCSC-NZ, CERT-NZ, NCSC-NL, and NCSC-UK do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply their endorsement, recommendation, or favoring.

Purpose

This document was developed by CISA, the FBI, NSA, CCCS, NCSC-NZ, CERT-NZ, NCSC-NL, and NCSC-UK in furtherance of their respective cybersecurity missions, including their responsibilities to develop and issue cybersecurity specifications and mitigations. This information may be shared broadly to reach all appropriate stakeholders. 

Source…

Protecting Against Cyber Threats to Managed Service Providers and their Customers


Tactical actions for MSPs and their customers to take today:
• Identify and disable accounts that are no longer in use.
• Enforce MFA on MSP accounts that access the customer environment and monitor for unexplained failed authentication.
• Ensure MSP-customer contracts transparently identify ownership of ICT security roles and responsibilities.

The cybersecurity authorities of the United Kingdom (NCSC-UK), Australia (ACSC), Canada (CCCS), New Zealand (NCSC-NZ), and the United States (CISA), (NSA), (FBI) are aware of recent reports that observe an increase in malicious cyber activity targeting managed service providers (MSPs) and expect this trend to continue.[1] This joint Cybersecurity Advisory (CSA) provides actions MSPs and their customers can take to reduce their risk of falling victim to a cyber intrusion. This advisory describes cybersecurity best practices for information and communications technology (ICT) services and functions, focusing on guidance that enables transparent discussions between MSPs and their customers on securing sensitive data. Organizations should implement these guidelines as appropriate to their unique environments, in accordance with their specific security needs, and in compliance with applicable regulations. MSP customers should verify that the contractual arrangements with their provider include cybersecurity measures in line with their particular security requirements.

The guidance provided in this advisory is specifically tailored for both MSPs and their customers and is the result of a collaborative effort from the United Kingdom National Cyber Security Centre (NCSC-UK), the Australian Cyber Security Centre (ACSC), the Canadian Centre for Cyber Security (CCCS), the New Zealand National Cyber Security Centre (NCSC-NZ), the United States’ Cybersecurity and Infrastructure Security Agency (CISA), National Security Agency (NSA), and Federal Bureau of Investigation (FBI) with contributions from industry members of the Joint Cyber Defense Collaborative (JCDC). Organizations should read this advisory in conjunction with NCSC-UK guidance on actions to take when the cyber threat is heightened, CCCS guidance on Cyber Security Considerations for Consumers of Managed Services, and CISA guidance provided on the Shields Up and Shields Up Technical Guidance webpages.

Managed Service Providers

This advisory defines MSPs as entities that deliver, operate, or manage ICT services and functions for their customers via a contractual arrangement, such as a service level agreement. In addition to offering their own services, an MSP may offer services in conjunction with those of other providers. Offerings may include platform, software, and IT infrastructure services; business process and support functions; and cybersecurity services. MSPs typically manage these services and functions in their customer’s network environment—either on the customer’s premises or hosted in the MSP’s data center. Note: this advisory does not address guidance on cloud service providers (CSPs)—providers who handle the ICT needs of their customers via cloud services such as Software-as-a-Service, Platform-as-a-Service, and Infrastructure-as-a-Service; however, MSPs may offer these services as well. (See Appendix for additional definitions.)

MSPs provide services that usually require both trusted network connectivity and privileged access to and from customer systems. Many organizations—ranging from large critical infrastructure organizations to small- and mid-sized businesses—use MSPs to manage ICT systems, store data, or support sensitive processes. Many organizations make use of MSPs to scale and support network environments and processes without expanding their internal staff or having to develop the capabilities internally. 

Threat Actors Targeting MSP Access to Customer Networks

Whether the customer’s network environment is on premises or externally hosted, threat actors can use a vulnerable MSP as an initial access vector to multiple victim networks, with globally cascading effects. The UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities expect malicious cyber actors—including state-sponsored advanced persistent threat (APT) groups—to step up their targeting of MSPs in their efforts to exploit provider-customer network trust relationships. For example, threat actors successfully compromising an MSP could enable follow-on activity—such as ransomware and cyber espionage—against the MSP as well as across the MSP’s customer base.

The UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities have previously issued general guidance for MSPs and their customers.[2],[3],[4],[5],[6],[7],[8] This advisory provides specific guidance to enable transparent, well-informed discussions between MSPs and their customers that center on securing sensitive information and data. These discussions should result in a re-evaluation of security processes and contractual commitments to accommodate customer risk tolerance. A shared commitment to security will reduce risk for both MSPs and their customers, as well as the global ICT community. 

Download the Joint Cybersecurity Advisory: Protecting Against Cyber Threats to Managed Service Providers and their Customers (pdf, 697kb).

Recommendations 

MSPs and their Customers

The UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities recommend MSPs and their customers implement the baseline security measures and operational controls listed in this section. Additionally, customers should ensure their contractual arrangements specify that their MSP implements these measures and controls.

Prevent initial compromise. 

In their efforts to compromise MSPs, malicious cyber actors exploit vulnerable devices and internet-facing services, conduct brute force attacks, and use phishing techniques. MSPs and their customers should ensure they are mitigating these attack methods. Useful mitigation resources on initial compromise attack methods are listed below:

  • Improve security of vulnerable devices.
  • Protect internet-facing services.
  • Defend against brute force and password spraying.
  • Defend against phishing.

Enable/improve monitoring and logging processes. 

It can be months before incidents are detected, so UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities recommend all organizations store their most important logs for at least six months. Whether through a comprehensive security information and event management (SIEM) solution or discrete logging tools, implement and maintain a segregated logging regime to detect threats to networks. Organizations can refer to the following NCSC-UK guidance on the appropriate data to collect for security purposes and when to use it: What exactly should we be logging? Additionally, all organizations—whether through contractual arrangements with an MSP or on their own—should implement endpoint detection and network defense monitoring capabilities in addition to using application allowlisting/denylisting. 

  • MSPs should log the delivery infrastructure activities used to provide services to the customer. MSPs should also log both internal and customer network activity, as appropriate and contractually agreed upon. 
  • Customers should enable effective monitoring and logging of their systems. If customers choose to engage an MSP to perform monitoring and logging, they should ensure that their contractual arrangements require their MSP to:
    • Implement comprehensive security event management that enables appropriate monitoring and logging of provider-managed customer systems; 
    • Provide visibility—as specified in the contractual arrangement—to customers of logging activities, including provider’s presence, activities, and connections to the customer networks (Note: customers should ensure that MSP accounts are properly monitored and audited.); and
    • Notify customer of confirmed or suspected security events and incidents occurring on the provider’s infrastructure and administrative networks, and send these to a security operations center (SOC) for analysis and triage. 

Enforce multifactor authentication (MFA). 

Organizations should secure remote access applications and enforce MFA where possible to harden the infrastructure that enables access to networks and systems.[9],[10] Note: Russian state-sponsored APT actors have recently demonstrated the ability to exploit default MFA protocols; organizations should review configuration policies to protect against “fail open” and re-enrollment scenarios.[11

  • MSPs should recommend the adoption of MFA across all customer services and products. Note: MSPs should also implement MFA on all accounts that have access to customer environments and should treat those accounts as privileged.
  • Customers should ensure that their contractual arrangements mandate the use of MFA on the services and products they receive. Contracts should also require MFA to be enforced on all MSP accounts used to access customer environments.

Manage internal architecture risks and segregate internal networks. 

Organizations should understand their environment and segregate their networks. Identify, group, and isolate critical business systems and apply appropriate network security controls to them to reduce the impact of a compromise across the organization.[12],[13]

  • MSPs should review and verify all connections between internal systems, customer systems, and other networks. Segregate customer data sets (and services, where applicable) from each other—as well as from internal company networks—to limit the impact of a single vector of attack. Do not reuse admin credentials across multiple customers. 
  • Customers should review and verify all connections between internal systems, MSP systems, and other networks. Ensure management of identity providers and trusts between the different environments. Use a dedicated virtual private network (VPN) or alternative secure access method, to connect to MSP infrastructure and limit all network traffic to and from the MSP to that dedicated secure connection. Verify that the networks used for trust relationships with MSPs are suitably segregated from the rest of their networks. Ensure contractual agreements specify that MSPs will not reuse admin credentials across multiple customers.

Apply the principle of least privilege. 

Organizations should apply the principle of least privilege throughout their network environment and immediate update privileges upon changes in administrative roles. Use a tiering model for administrative accounts so that these accounts do not have any unnecessary access or privileges. Only use accounts with full privileges across an enterprise when strictly necessary and consider the use of time-based privileges to further restrict their use. Identify high-risk devices, services and users to minimize their accesses.[14]

  • MSPs should apply this principle to both internal and customer environments, avoiding default administrative privileges. 
  • Customers should ensure that their MSP applies this principle to both provider and customer network environments. Note: customers with contractual arrangements that provide them with administration of MSP accounts within their environment should ensure that the MSP accounts only have access to the services/resources being managed by the MSP.

Deprecate obsolete accounts and infrastructure. 

Both MSPs and customers should periodically review their internet attack surface and take steps to limit it, such as disabling user accounts when personnel transition.[15] (Note: although sharing accounts is not recommended, should an organization require this, passwords to shared account should be reset when personnel transition.) Organizations should also audit their network infrastructure—paying particular attention to those on the MSP-customer boundary—to identify and disable unused systems and services. Port scanning tools and automated system inventories can assist organizations in confirming the roles and responsibilities of systems.

  • Customers should be sure to disable MSP accounts that are no longer managing infrastructure. Note: disabling MSP accounts can be overlooked when a contract terminates.

Apply updates. 

Organizations should update software, including operating systems, applications, and firmware. Prioritize applying security updates to software containing known exploited vulnerabilities. Note: organizations should prioritize patching vulnerabilities included in CISA’s catalogue of known exploited vulnerabilities (KEV) as opposed to only those with high Common Vulnerability Scoring System (CVSS) scores that have not been exploited and may never be exploited.[16],[17],[18],[19]

  • MSPs should implement updates on internal networks as quickly as possible.
  • Customers should ensure that they understand their MSP’s policy on software updates and request that comprehensive and timely updates are delivered as an ongoing service.

Backup systems and data. 

Organizations should regularly update and test backups—including “gold images” of critical systems in the event these need to be rebuilt (Note: organizations should base the frequency of backups on their recovery point objective [20]). Store backups separately and isolate them from network connections that could enable the spread of ransomware; many ransomware variants attempt to find and encrypt/delete accessible backups. Isolating backups enables restoration of systems/data to their previous state should they be encrypted with ransomware. Note: best practices include storing backups separately, such as on external media.[21],[22],[23

  • MSPs should regularly backup internal data as well as customer data (where contractually appropriate) and maintain offline backups encrypted with separate, offline encryption keys. Providers should encourage customers to create secure, offsite backups and exercise recovery capabilities.
  • Customers should ensure that their contractual arrangements include backup services that meet their resilience and disaster recovery requirements. Specifically, customers should require their MSP to implement a backup solution that automatically and continuously backs up critical data and system configurations and store backups in an easily retrievable location, e.g., a cloud-based solution or a location that is air-gapped from the organizational network.

Develop and exercise incident response and recovery plans. 

Incident response and recovery plans should include roles and responsibilities for all organizational stakeholders, including executives, technical leads, and procurement officers. Organizations should maintain up-to-date hard copies of plans to ensure responders can access them should the network be inaccessible (e.g., due to a ransomware attack).[24]

  • MSPs should develop and regularly exercise internal incident response and recovery plans and encourage customers to do the same.
  • Customers should ensure that their contractual arrangements include incident response and recovery plans that meet their resilience and disaster recovery requirements. Customers should ensure these plans are tested at regular intervals.

Understand and proactively manage supply chain risk. 

All organizations should proactively manage ICT supply chain risk across security, legal, and procurement groups, using risk assessments to identify and prioritize the allocation of resources.[25],[26]

  • MSPs should understand their own supply chain risk and manage the cascading risks it poses to customers.
  • Customers should understand the supply chain risk associated with their MSP, including risk associated with third-party vendors or subcontractors. Customers should also set clear network security expectations with their MSPs and understand the access their MSP has to their network and the data it houses. Each customer should ensure their contractual arrangements meet their specific security requirements and that their contract specifies whether the MSP or the customer owns specific responsibilities, such as hardening, detection, and incident response.[27]

Promote transparency. 

Both MSPs and their customers will benefit from contractual arrangements that clearly define responsibilities. 

  • MSPs, when negotiating the terms of a contract with their customer, should provide clear explanations of the services the customer is purchasing, services the customer is not purchasing, and all contingencies for incident response and recovery.
  • Customers should ensure that they have a thorough understanding of the security services their MSP is providing via the contractual arrangement and address any security requirements that fall outside the scope of the contract. Note: contracts should detail how and when MSPs notify the customer of an incident affecting the customer’s environment.

Manage account authentication and authorization. 

All organizations should adhere to best practices for password and permission management. [28],[29],[30] Organizations should review logs for unexplained failed authentication attempts—failed authentication attempts directly following an account password change could indicate that the account had been compromised. Note: network defenders can proactively search for such “intrusion canaries” by reviewing logs after performing password changes—using off-network communications to inform users of the changes—across all sensitive accounts. (See the ACSC publication, Windows Event Logging and Forwarding as well as Microsoft’s documentation, 4625(F): An account failed to log on, for additional guidance.) 

  • MSPs should verify that the customer restricts MSP account access to systems managed by the MSP.
  • Customers should ensure MSP accounts are not assigned to internal administrator groups; instead, restrict MSP accounts to systems managed by the MSP. Grant access and administrative permissions on a need-to-know basis, using the principle of least privilege. Verify, via audits, that MSP accounts are being used for appropriate purposes and activities, and that these accounts are disabled when not actively being used. 

Purpose

This advisory was developed by UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities in furtherance their respective cybersecurity missions, including their responsibilities to develop and issue cybersecurity specifications and mitigations.

Acknowledgements

The UK, Australian, Canadian, New Zealand, and U.S. cybersecurity authorities would like to thank Secureworks for their contributions to this CSA.

Disclaimer

The information in this report is being provided “as is” for informational purposes only. NCSC-UK, ACSC, CCCS, NCSC-NZ, CISA, NSA, and FBI do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favouring.

Source…

2021 Top Routinely Exploited Vulnerabilities


This joint Cybersecurity Advisory (CSA) was coauthored by cybersecurity authorities of the United States, Australia, Canada, New Zealand, and the United Kingdom: the Cybersecurity and Infrastructure Security Agency (CISA), National Security Agency (NSA), Federal Bureau of Investigation (FBI), Australian Cyber Security Centre (ACSC), Canadian Centre for Cyber Security (CCCS), New Zealand National Cyber Security Centre (NZ NCSC), and United Kingdom’s National Cyber Security Centre (NCSC-UK). This advisory provides details on the top 15 Common Vulnerabilities and Exposures (CVEs) routinely exploited by malicious cyber actors in 2021, as well as other CVEs frequently exploited.

U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities assess, in 2021, malicious cyber actors aggressively targeted newly disclosed critical software vulnerabilities against broad target sets, including public and private sector organizations worldwide. To a lesser extent, malicious cyber actors continued to exploit publicly known, dated software vulnerabilities across a broad spectrum of targets. 

The cybersecurity authorities encourage organizations to apply the recommendations in the Mitigations section of this CSA. These mitigations include applying timely patches to systems and implementing a centralized patch management system to reduce the risk of compromise by malicious cyber actors.

Click here for a PDF version of this report. 

Key Findings

Globally, in 2021, malicious cyber actors targeted internet-facing systems, such as email servers and virtual private network (VPN) servers, with exploits of newly disclosed vulnerabilities. For most of the top exploited vulnerabilities, researchers or other actors released proof of concept (POC) code within two weeks of the vulnerability’s disclosure, likely facilitating exploitation by a broader range of malicious actors.

To a lesser extent, malicious cyber actors continued to exploit publicly known, dated software vulnerabilities—some of which were also routinely exploited in 2020 or earlier. The exploitation of older vulnerabilities demonstrates the continued risk to organizations that fail to patch software in a timely manner or are using software that is no longer supported by a vendor.

Top 15 Routinely Exploited Vulnerabilities

Table 1 shows the top 15 vulnerabilities U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities observed malicious actors routinely exploiting in 2021, which include:

  • CVE-2021-44228. This vulnerability, known as Log4Shell, affects Apache’s Log4j library, an open-source logging framework. An actor can exploit this vulnerability by submitting a specially crafted request to a vulnerable system that causes that system to execute arbitrary code. The request allows a cyber actor to take full control over the system. The actor can then steal information, launch ransomware, or conduct other malicious activity.[1] Log4j is incorporated into thousands of products worldwide. This vulnerability was disclosed in December 2021; the rapid widespread exploitation of this vulnerability demonstrates the ability of malicious actors to quickly weaponize known vulnerabilities and target organizations before they patch.
  • CVE-2021-26855, CVE-2021-26858, CVE-2021-26857, CVE-2021-27065. These vulnerabilities, known as ProxyLogon, affect Microsoft Exchange email servers. Successful exploitation of these vulnerabilities in combination (i.e., “vulnerability chaining”) allows an unauthenticated cyber actor to execute arbitrary code on vulnerable Exchange Servers, which, in turn, enables the actor to gain persistent access to files and mailboxes on the servers, as well as to credentials stored on the servers. Successful exploitation may additionally enable the cyber actor to compromise trust and identity in a vulnerable network.
  • CVE-2021-34523, CVE-2021-34473, CVE-2021-31207. These vulnerabilities, known as ProxyShell, also affect Microsoft Exchange email servers. Successful exploitation of these vulnerabilities in combination enables a remote actor to execute arbitrary code. These vulnerabilities reside within the Microsoft Client Access Service (CAS), which typically runs on port 443 in Microsoft Internet Information Services (IIS) (e.g., Microsoft’s web server). CAS is commonly exposed to the internet to enable users to access their email via mobile devices and web browsers. 
  • CVE-2021-26084. This vulnerability, affecting Atlassian Confluence Server and Data Center, could enable an unauthenticated actor to execute arbitrary code on vulnerable systems. This vulnerability quickly became one of the most routinely exploited vulnerabilities after a POC was released within a week of its disclosure. Attempted mass exploitation of this vulnerability was observed in September 2021.

Three of the top 15 routinely exploited vulnerabilities were also routinely exploited in 2020: CVE-2020-1472, CVE-2018-13379, and CVE-2019-11510. Their continued exploitation indicates that many organizations fail to patch software in a timely manner and remain vulnerable to malicious cyber actors.

Table 1: Top 15 Routinely Exploited Vulnerabilities in 2021

Additional Routinely Exploited Vulnerabilities

In addition to the 15 vulnerabilities listed in table 1, U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities identified vulnerabilities, listed in table 2, that were also routinely exploited by malicious cyber actors in 2021. 

These vulnerabilities include multiple vulnerabilities affecting internet-facing systems, including Accellion File Transfer Appliance (FTA), Windows Print Spooler, and Pulse Secure Pulse Connect Secure. Three of these vulnerabilities were also routinely exploited in 2020: CVE-2019-19781, CVE-2019-18935, and CVE-2017-11882.

Table 2: Additional Routinely Exploited Vulnerabilities in 2021

Vulnerability and Configuration Management

  • Update software, operating systems, applications, and firmware on IT network assets in a timely manner. Prioritize patching known exploited vulnerabilities, especially those CVEs identified in this CSA, and then critical and high vulnerabilities that allow for remote code execution or denial-of-service on internet-facing equipment. For patch information on CVEs identified in this CSA, refer to the appendix. 
    • If a patch for a known exploited or critical vulnerability cannot be quickly applied, implement vendor-approved workarounds.
  • Use a centralized patch management system.
  • Replace end-of-life software, i.e., software that is no longer supported by the vendor. For example, Accellion FTA was retired in April 2021.
  • Organizations that are unable to perform rapid scanning and patching of internet-facing systems should consider moving these services to mature, reputable cloud service providers (CSPs) or other managed service providers (MSPs). Reputable MSPs can patch applications—such as webmail, file storage, file sharing, and chat and other employee collaboration tools—for their customers. However, as MSPs and CSPs expand their client organization’s attack surface and may introduce unanticipated risks, organizations should proactively collaborate with their MSPs and CSPs to jointly reduce that risk. For more information and guidance, see the following resources.

Identity and Access Management

  • Enforce multifactor authentication (MFA) for all users, without exception.
  • Enforce MFA on all VPN connections. If MFA is unavailable, require employees engaging in remote work to use strong passwords. 
  • Regularly review, validate, or remove privileged accounts (annually at a minimum).
  • Configure access control under the concept of least privilege principle.
    • Ensure software service accounts only provide necessary permissions (least privilege) to perform intended functions (non-administrative privileges).

Note: see CISA Capacity Enhancement Guide – Implementing Strong Authentication and ACSC guidance on Implementing Multi-Factor Authentication for more information on hardening authentication systems.

Protective Controls and Architecture 

  • Properly configure and secure internet-facing network devices, disable unused or unnecessary network ports and protocols, encrypt network traffic, and disable unused network services and devices. 
    • Harden commonly exploited enterprise network services, including Link-Local Multicast Name Resolution (LLMNR) protocol, Remote Desktop Protocol (RDP), Common Internet File System (CIFS), Active Directory, and OpenLDAP.
    • Manage Windows Key Distribution Center (KDC) accounts (e.g., KRBTGT) to minimize Golden Ticket attacks and Kerberoasting.
    • Strictly control the use of native scripting applications, such as command-line, PowerShell, WinRM, Windows Management Instrumentation (WMI), and Distributed Component Object Model (DCOM).
  • Segment networks to limit or block lateral movement by controlling access to applications, devices, and databases. Use private virtual local area networks. 
  • Continuously monitor the attack surface and investigate abnormal activity that may indicate lateral movement of a threat actor or malware.
    • Use security tools, such as endpoint detection and response (EDR) and security information and event management (SIEM) tools. Consider using an information technology asset management (ITAM) solution to ensure your EDR, SIEM, vulnerability scanner etc., are reporting the same number of assets.
    • Monitor the environment for potentially unwanted programs.
  • Reduce third-party applications and unique system/application builds; provide exceptions only if required to support business critical functions.
  • Implement application allowlisting. 

Resources

Disclaimer

The information in this report is being provided “as is” for informational purposes only. CISA, the FBI, NSA, ACSC, CCCS, NZ NCSC, and NCSC-UK do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring.

Purpose 

This document was developed by U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities in furtherance of their respective cybersecurity missions, including their responsibilities to develop and issue cybersecurity specifications and mitigations.

References

[1] CISA’s Apache Log4j Vulnerability Guidance

Appendix: Patch Information and Additional Resources for  Top Exploited Vulnerabilities

CVE

Vendor

Affected Products

Patch Information

Resources

CVE-2021-42237

Sitecore

Sitecore XP 7.5.0 – Sitecore XP 7.5.2

Sitecore XP 8.0.0 – Sitecore XP 8.2.7

Sitecore Security Bulletin SC2021-003-499266

ACSC Alert Active Exploitation of vulnerable Sitecore Experience Platform Content Management Systems

 

CVE-2021-35464

ForgeRock

Access Management (AM) 5.x, 6.0.0.x, 6.5.0.x, 6.5.1, 6.5.2.x and 6.5.3

OpenAM 9.x, 10.x, 11.x, 12.x and 13.x

ForgeRock AM Security Advisory #202104

ACSC Advisory Active exploitation of ForgeRock Access Manager / OpenAM servers

CCCS ForgeRock Security Advisory

CVE-2021-27104

Accellion

FTA 9_12_370 and earlier

Accellion Press Release: Update to Recent FTA Security Incident

Joint CSA Exploitation of Accellion File Transfer Appliance

ACSC Alert Potential Accellion File Transfer Appliance compromise

 

 

CVE-2021-27103

FTA 9_12_411 and earlier

CVE-2021-27102

FTA versions 9_12_411 and earlier

CVE-2021-27101

FTA 9_12_370 and earlier

 

CVE-2021-21985

VMware

vCenter Server 7.0, 6.7, 6.5

Cloud Foundation (vCenter Server) 4.x and 3.x

VMware Advisory VMSA-2021-0010

CCCS VMware Security Advisory

CVE-2021-21972

VMware

vCenter Server 7.0, 6.7, 6.5

Cloud Foundation (vCenter Server) 4.x and 3.x

VMware Advisory VMSA-2021-0002

ACSC Alert VMware vCenter Server plugin remote code execution vulnerability

CCCS VMware Security Advisory

CCCS Alert APT Actors Target U.S. and Allied Networks – Update 1

CVE-2021-20038

SonicWall

SMA 100 Series (SMA 200, 210, 400, 410, 500v), versions 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv

SonicWall Security Advisory SNWLID-2021-0026

ACSC Alert Remote code execution vulnerability present in SonicWall SMA 100 series appliances

CCCS SonicWall Security Advisory

 

CVE-2021-44228

Apache

Log4j, all versions from 2.0-beta9 to 2.14.1

For other affected vendors and products, see CISA’s GitHub repository.

Log4j: Apache Log4j Security Vulnerabilities

For additional information, see joint CSA: Mitigating Log4Shell and Other Log4j-Related Vulnerabilities

CISA webpage Apache Log4j Vulnerability Guidance

CCCS Active exploitation of Apache Log4j vulnerability – Update 7

CVE-2021-40539

Zoho ManageEngine

ADSelfService Plus version 6113 and prior

Zoho ManageEngine: ADSelfService Plus 6114 Security Fix Release

Joint CSA APT Actors Exploiting Newly Identified Vulnerability in ManageEngine ADSelfService Plus

CCCS Zoho Security Advisory

CVE-2021-40444

Microsoft

Multiple Windows products; see Microsoft Security Update Guide: MSHTML Remote Code Execution Vulnerability, CVE-2021-40444

Microsoft Security Update Guide: MSHTML Remote Code Execution Vulnerability, CVE-2021-40444

 

CVE-2021-34527

Microsoft

Multiple Windows products; see Microsoft Security Update Guide: Windows Print Spooler Remote Code Execution Vulnerability, CVE-2021-34527

Microsoft Security Update Guide: Windows Print Spooler Remote Code Execution Vulnerability, CVE-2021-34527

Joint CSA Russian State-Sponsored Cyber Actors Gain Network Access by Exploiting Default Multifactor Authentication Protocols and “PrintNightmare” Vulnerability

CCCS Alert Windows Print Spooler Vulnerability Remains Unpatched – Update 3

CVE-2021-34523

Microsoft

Microsoft Exchange Server 2013 Cumulative Update 23

Microsoft Exchange Server 2016 Cumulative Updates 19 and 20

Microsoft Exchange Server 2019 Cumulative Updates 8 and 9

Microsoft Security Update Guide: Microsoft Exchange Server Elevation of Privilege Vulnerability, CVE-2021-34523

Joint CSA Iranian Government-Sponsored APT Cyber Actors Exploiting Microsoft Exchange and Fortinet Vulnerabilities in Furtherance of Malicious Activities

ACSC Alert Microsoft Exchange ProxyShell Targeting in Australia

 

CVE-2021-34473

Microsoft

Multiple Exchange Server versions; see: Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-34473

Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-34473

CVE-2021-31207

Microsoft

Multiple Exchange Server versions; see Microsoft Update Guide: Microsoft Exchange Server Security Feature Bypass Vulnerability, CVE-2021-31207

Microsoft Update Guide: Microsoft Exchange Server Security Feature Bypass Vulnerability, CVE-2021-31207

CVE-2021-3156

Sudo

Sudo before 1.9.5p2

Sudo Stable Release 1.9.5p2

 

CVE-2021-27852

Checkbox Survey

Checkbox Survey versions prior to 7

 

 

CVE-2021-27065

Microsoft Exchange Server

Multiple versions; see: Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-27065

Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-27065

CISA Alert: Mitigate Microsoft Exchange Server Vulnerabilities

ACSC Advisory Active exploitation of Vulnerable Microsoft Exchange servers

CCCS Alert Active Exploitation of Microsoft Exchange Vulnerabilities – Update 4

CVE-2021-26858

Microsoft

Exchange Server, multiple versions; see Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26858

Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26858

CVE-2021-26857

Microsoft

Exchange Server, multiple versions; see Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26857

Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26857

CVE-2021-26855

Microsoft

Exchange Server, multiple versions; see Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26855

Microsoft Security Update Guide: Microsoft Exchange Server Remote Code Execution Vulnerability, CVE-2021-26855

CVE-2021-26084

 

Jira Atlassian

Confluence Server and Data Center, versions 6.13.23, from version 6.14.0 before 7.4.11, from version 7.5.0 before 7.11.6, and from version 7.12.0 before 7.12.5.

Jira Atlassian: Confluence Server Webwork OGNL injection – CVE-2021-26084

ACSC Alert Remote code execution vulnerability present in certain versions of Atlassian Confluence

CCCS Atlassian Security Advisory

CVE-2021-22893

Pulse Secure

PCS 9.0R3/9.1R1 and Higher

Pulse Secure SA44784 – 2021-04: Out-of-Cycle Advisory: Multiple Vulnerabilities Resolved in Pulse Connect Secure 9.1R11.4

CCCS Alert  Active Exploitation of Pulse Connect Secure Vulnerabilities – Update 1

CVE-2021-20016

SonicWall

SMA 100 devices (SMA 200, SMA 210, SMA 400, SMA 410, SMA 500v)

SonicWall Security Advisory SNWLID-2021-0001

 

CVE-2021-1675

Microsoft

Multiple Windows products; see Microsoft Security Update Guide Windows Print Spooler Remote Code Execution Vulnerability, CVE-2021-1675

Microsoft Security Update Guide: Windows Print Spooler Remote Code Execution Vulnerability, CVE-2021-1675

CCCS Alert Windows Print Spooler Vulnerability Remains Unpatched – Update 3

CVE-2020-2509

QNAP

QTS, multiple versions; see QNAP: Command Injection Vulnerability in QTS and QuTS hero

QuTS hero h4.5.1.1491 build 20201119 and later

QNAP: Command Injection Vulnerability in QTS and QuTS hero

 

CVE-2020-1472

Microsoft

Windows Server, multiple versions; see Microsoft Security Update Guide: Netlogon Elevation of Privilege Vulnerability, CVE-2020-1472

Microsoft Security Update Guide: Netlogon Elevation of Privilege Vulnerability, CVE-2020-1472

ACSC Alert Netlogon elevation of privilege vulnerability (CVE-2020-1472)

Joint CSA APT Actors Chaining Vulnerabilities Against SLTT, Critical Infrastructure, and Elections Organizations

CCCS Alert Microsoft Netlogon Elevation of Privilege Vulnerability – CVE-2020-1472 – Update 1

CVE-2020-0688

Microsoft

Exchange Server, multiple versions; see Microsoft Security Update Guide: Microsoft Exchange Validation Key Remote Code Execution Vulnerability, CVE-2020-0688

Microsoft Security Update Guide: Microsoft Exchange Validation Key Remote Code Execution Vulnerability, CVE-2020-0688

CISA Alert Chinese Ministry of State Security-Affiliated Cyber Threat Actor Activity

Joint CSA Russian State-Sponsored Cyber Actors Target Cleared Defense Contractor Networks to Obtain Sensitive U.S. Defense Information and Technology

CCCS Alert Microsoft Exchange Validation Key Remote Code Execution Vulnerability

CVE-2019-19781

Citrix

ADC and Gateway version 13.0 all supported builds before 13.0.47.24

NetScaler ADC and NetScaler Gateway, version 12.1 all supported builds before 12.1.55.18; version 12.0 all supported builds before 12.0.63.13; version 11.1 all supported builds before 11.1.63.15; version 10.5 all supported builds before 10.5.70.12

SD-WAN WANOP appliance models 4000-WO, 4100-WO, 5000-WO, and 5100-WO all supported software release builds before 10.2.6b and 11.0.3b

Citrix Security Bulletin CTX267027

Joint CSA APT Actors Chaining Vulnerabilities Against SLTT, Critical Infrastructure, and Elections Organizations

CISA Alert Chinese Ministry of State Security-Affiliated Cyber Threat Actor Activity

CCCS Alert Detecting Compromises relating to Citrix CVE-2019-19781

 

 

 

CVE-2019-18935

Progress Telerik

UI for ASP.NET AJAX through 2019.3.1023

Telerik UI for ASP.NET AJAX Allows JavaScriptSerializer Deserialization

ACSC Alert Active exploitation of vulnerability in Microsoft Internet Information Services

 

CVE-2019-11510

Pulse Secure

Pulse Connect Secure 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4

Pulse Secure: SA44101 – 2019-04: Out-of-Cycle Advisory: Multiple vulnerabilities resolved in Pulse Connect Secure / Pulse Policy Secure 9.0RX

CISA Alert Continued Exploitation of Pulse Secure VPN Vulnerability

CISA Alert Chinese Ministry of State Security-Affiliated Cyber Threat Actor Activity

ACSC Advisory Recommendations to mitigate vulnerability in Pulse Connect Secure VPN Software

Joint CSA APT Actors Chaining Vulnerabilities Against SLTT, Critical Infrastructure, and Elections Organizations

CCCS Alert APT Actors Target U.S. and Allied Networks – Update 1

CVE-2018-13379

Fortinet

FortiProxy 2.0.2, 2.0.1, 2.0.0, 1.2.8, 1.2.7, 1.2.6, 1.2.5, 1.2.4, 1.2.3, 1.2.2, 1.2.1, 1.2.0, 1.1.6

Fortinet FortiGuard Labs: FG-IR-20-233

Joint CSA Russian State-Sponsored Cyber Actors Target Cleared Defense Contractor Networks to Obtain Sensitive U.S. Defense Information and Technology

Joint CSA Iranian Government-Sponsored APT Cyber Actors Exploiting Microsoft Exchange and Fortinet Vulnerabilities in Furtherance of Malicious Activities

Joint CSA APT Actors Chaining Vulnerabilities Against SLTT, Critical Infrastructure, and Elections Organizations

ACSC Alert APT exploitation of Fortinet Vulnerabilities

CCCS Alert Exploitation of Fortinet FortiOS vulnerabilities (CISA, FBI) – Update 1

CVE-2018-0171

Cisco

See Cisco Security Advisory: cisco-sa-20180328-smi2

Cisco Security Advisory: cisco-sa-20180328-smi2

CCCS Action Required to Secure the Cisco IOS and IOS XE Smart Install Feature

CVE-2017-11882

Microsoft

Office, multiple versions; see Microsoft Security Update Guide: Microsoft Office Memory Corruption Vulnerability, CVE-2017-11882

Microsoft Security Update Guide: Microsoft Office Memory Corruption Vulnerability, CVE-2017-11882

CCCS Alert Microsoft Office Security Update

CVE-2017-0199

Microsoft

Multiple products; see Microsoft Security Update Guide: Microsoft Office/WordPad Remote Code Execution Vulnerability w/Windows, CVE-2017-0199

Microsoft Security Update Guide: Microsoft Office/WordPad Remote Code Execution Vulnerability w/Windows, CVE-2017-0199

CCCS Microsoft Security Updates

Source…

Russian State-Sponsored and Criminal Cyber Threats to Critical Infrastructure


Russian State-Sponsored Cyber Operations

Russian state-sponsored cyber actors have demonstrated capabilities to compromise IT networks; develop mechanisms to maintain long-term, persistent access to IT networks; exfiltrate sensitive data from IT and operational technology (OT) networks; and disrupt critical industrial control systems (ICS)/OT functions by deploying destructive malware. 
Historical operations have included deployment of destructive malware—including BlackEnergy and NotPetya—against Ukrainian government and critical infrastructure organizations. Recent Russian state-sponsored cyber operations have included DDoS attacks against Ukrainian organizations. Note: for more information on Russian state-sponsored cyber activity, including known TTPs, see joint CSA Understanding and Mitigating Russian State-Sponsored Cyber Threats to U.S. Critical Infrastructure

Cyber threat actors from the following Russian government and military organizations have conducted malicious cyber operations against IT and/or OT networks:

  • The Russian Federal Security Service (FSB), including FSB’s Center 16 and Center 18
  • Russian Foreign Intelligence Service (SVR)
  • Russian General Staff Main Intelligence Directorate (GRU), 85th Main Special Service Center (GTsSS)
  • GRU’s Main Center for Special Technologies (GTsST)
  • Russian Ministry of Defense, Central Scientific Institute of Chemistry and Mechanics (TsNIIKhM)

The Russian Federal Security Service

Overview: FSB, the KGB’s successor agency, has conducted malicious cyber operations targeting the Energy Sector, including UK and U.S. energy companies, U.S. aviation organizations, U.S. government and military personnel, private organizations, cybersecurity companies, and journalists. FSB has been known to task criminal hackers for espionage-focused cyber activity; these same hackers have separately been responsible for disruptive ransomware and phishing campaigns.

Industry reporting identifies three intrusion sets associated with the FSB, but the U.S. and UK governments have only formally attributed one of these sets—known as BERSERK BEAR—to FSB.

  • BERSERK BEAR (also known as Crouching Yeti, Dragonfly, Energetic Bear, and Temp.Isotope) has, according to industry reporting, historically targeted entities in Western Europe and North America including state, local, tribal, and territorial (SLTT) organizations, as well as Energy, Transportation Systems, and Defense Industrial Base (DIB) Sector organizations. This group has also targeted the Water and Wastewater Systems Sector and other critical infrastructure facilities. Common TTPs include scanning to exploit internet-facing infrastructure and network appliances, conducting brute force attacks against public-facing web applications, and leveraging compromised infrastructure—often websites frequented or owned by their target—for Windows New Technology Local Area Network Manager (NTLM) credential theft. Industry reporting assesses that this actor has a destructive mandate.

The U.S. and UK governments assess that this APT group is almost certainly FSB’s Center 16, or Military Unit 71330, and that FSB’s Center 16 has conducted cyber operations against critical IT systems and infrastructure in Europe, the Americas, and Asia. 

Resources: for more information on BERSERK BEAR, see the MITRE ATT&CK® webpage on Dragonfly.

High-Profile Activity: in 2017, FSB employees, including one employee in the FSB Center for Information Security (also known as Unit 64829 and Center 18), were indicted by the U.S. Department of Justice (DOJ) for accessing email accounts of U.S. government and military personnel, private organizations, and cybersecurity companies, as well as email accounts of journalists critical of the Russian government.[9] More recently, in 2021, FSB Center 16 officers were indicted by the U.S. DOJ for their involvement in a multi-stage campaign in which they gained remote access to U.S. and international Energy Sector networks, deployed ICS-focused malware, and collected and exfiltrated enterprise and ICS-related data. One of the victims was a U.S. nuclear power plant.[10

Resources: for more information on FSB, see: 

Russian Foreign Intelligence Service

Overview: SVR has operated an APT group since at least 2008 that has targeted multiple critical infrastructure organizations. SVR cyber threat actors have used a range of initial exploitation techniques that vary in sophistication coupled with stealthy intrusion tradecraft within compromised networks. SVR cyber actors’ novel tooling and techniques include:

  • Custom, sophisticated multi-platform malware targeting Windows and Linux systems (e.g., GoldMax and TrailBlazer); and
  • Lateral movement via the “credential hopping” technique, which includes browser cookie theft to bypass multifactor authentication (MFA) on privileged cloud accounts.[11]

High-Profile Activity: the U.S. Government, the Government of Canada, and the UK Government assess that SVR cyber threat actors were responsible for the SolarWinds Orion supply chain compromise and the associated campaign that affected U.S. government agencies, critical infrastructure entities, and private sector organizations.[12][13][14]

Also known as: APT29, COZY BEAR, CozyDuke, Dark Halo, The Dukes, NOBELIUM, and NobleBaron, StellarParticle, UNC2452, YTTRIUM [15]

Resources: for more information on SVR, see:

For more information on the SolarWinds Orion supply chain compromise, see:

GRU, 85th Main Special Service Center

Overview: GTsSS, or Unit 26165, is an APT group that has operated since at least 2004 and primarily targets government organizations, travel and hospitality entities, research institutions, and non-governmental organizations, in addition to other critical infrastructure organizations. 

According to industry reporting, GTsSS cyber actors frequently collect credentials to gain initial access to target organizations. GTsSS actors have collected victim credentials by sending spearphishing emails that appear to be legitimate security alerts from the victim’s email provider and include hyperlinks leading to spoofed popular webmail services’ logon pages. GTsSS actors have also registered domains to conduct credential harvesting operations. These domains mimic popular international social media platforms and masquerade as tourism- and sports-related entities and music and video streaming services.

High-Profile Activity: the U.S. Government assesses that GTsSS cyber actors have deployed Drovorub malware against victim devices as part of their cyber espionage operations.[16] The U.S. Government and UK Government assess that GTsSS actors used a Kubernetes® cluster to conduct widespread, distributed, and anonymized brute force access attempts against hundreds of government and private sector targets worldwide.[17

Also known as: APT28, FANCY BEAR, Group 74, IRON TWILIGHT, PawnStorm, Sednit, SNAKEMACKEREL, Sofacy, STRONTIUM, Swallowtail, TG-4127, Threat Group-4127, and Tsar Team [18]

Resources: for more information on GTsSS, see the MITRE ATT&CK webpage on APT28

GRU’s Main Center of Special Technologies

Overview: GTsST, or Unit 74455, is an APT group that has operated since at least 2009 and has targeted a variety of critical infrastructure organizations, including those in the Energy, Transportation Systems, and Financial Services Sectors. According to industry reporting, GTsST also has an extensive history of conducting cyber espionage as well as destructive and disruptive operations against NATO member states, Western government and military organizations, and critical infrastructure-related organizations, including in the Energy Sector.

The primary distinguishing characteristic of the group is its operations use techniques aimed at causing disruptive or destructive effects at targeted organizations using DDoS attacks or wiper malware. The group’s destructive operations have also leveraged wiper malware that mimics ransomware or hacktivism and can result in collateral effects to organizations beyond the primary intended targets. Some of their disruptive operations have shown disregard or ignorance of potential secondary or tertiary effects. 

High-Profile Activity: the malicious activity below has been previously attributed to GTsST by the U.S. Government and the UK Government.[19][20]

The U.S. Government, the Government of Canada, and UK Government have also attributed the October 2019 large-scale, disruptive cyber operations against a range of Georgian web hosting providers to GTsST. This activity resulted in websites—including sites belonging to the Georgian government, courts, non-government organizations (NGOs), media, and businesses—being defaced and interrupted the service of several national broadcasters.[21]22][23]

Also known as: ELECTRUM, IRON VIKING, Quedagh, the Sandworm Team, Telebots, VOODOO BEAR [24]

Resources: for more information on GTsST, see the MITRE ATT&CK webpage on Sandworm Team

Russian Ministry of Defense, Central Scientific Institute of Chemistry and Mechanics 

Overview: TsNIIKhM, as described on their webpage, is a research organization under Russia’s Ministry of Defense (MOD). Actors associated with TsNIIKhM have developed destructive ICS malware.

High-Profile Activity: TsNIIKhM has been sanctioned by the U.S. Department of the Treasury for connections to the destructive Triton malware (also called HatMan and TRISIS); TsNIIKhM has been sanctioned by the UK Foreign, Commonwealth, and Development Office (FCDO) for a 2017 incident that involved safety override controls (with Triton malware) in a foreign oil refinery.[25][26] In 2021, the U.S. DOJ indicted a TsNIIKhM Applied Development Center (ADC) employee for conducting computer intrusions against U.S. Energy Sector organizations. The indicted employee also accessed the systems of a foreign oil refinery and deployed Triton malware.[27] Triton is a custom-built malware designed to manipulate safety instrumented systems within ICS controllers, disabling the safety alarms that prevent dangerous conditions. 

Also known as: Temp.Veles, XENOTIME [28]

Resources: for more information on TsNIIKhM, see the MITRE ATT&CK webpage on TEMP.Veles. For more information on Triton, see:

Russian-Aligned Cyber Threat Groups

In addition to the APT groups identified in the Russian State-Sponsored Cyber Operations section, industry reporting identifies two intrusion sets—PRIMITIVE BEAR and VENOMOUS BEAR—as state-sponsored APT groups, but U.S., Australian, Canadian, New Zealand, and UK cyber authorities have not attributed these groups to the Russian government.

  • PRIMITIVE BEAR has, according to industry reporting, targeted Ukrainian organizations since at least 2013. This activity includes targeting Ukrainian government, military, and law enforcement entities using high-volume spearphishing campaigns to deliver its custom malware. According to industry reporting, PRIMITIVE BEAR conducted multiple cyber operations targeting Ukrainian organizations in the lead up to Russia’s invasion.

Resources: for more information on PRIMITIVE BEAR, see the MITRE ATT&CK webpage on the Gamaredon Group.

  • VENOMOUS BEAR has, according to industry reporting, historically targeted governments aligned with the North Atlantic Treaty Organization (NATO), defense contractors, and other organizations of intelligence value. Venomous Bear is known for its unique use of hijacked satellite internet connections for command and control (C2). It is also known for the hijacking of other non-Russian state-sponsored APT actor infrastructure.[29] VENOMOUS BEAR has also historically leveraged compromised infrastructure and maintained an arsenal of custom-developed sophisticated malware families, which is extremely complex and interoperable with variants developed over time. VENOMOUS BEAR has developed tools for multiple platforms, including Windows, Mac, and Linux.[30

Resources: for more information on VENOMOUS BEAR, see the MITRE ATT&CK webpage on Turla.

Russian-Aligned Cybercrime Groups

Cybercrime groups are typically financially motivated cyber actors that seek to exploit human or security vulnerabilities to enable direct theft of money (e.g., by obtaining bank login information) or by extorting money from victims. These groups pose consistent threats to critical infrastructure organizations globally. 

Since Russia’s invasion of Ukraine in February 2022, some cybercrime groups have independently publicly pledged support for the Russian government or the Russian people and/or threatened to conduct cyber operations to retaliate against perceived attacks against Russia or materiel support for Ukraine. These Russian-aligned cybercrime groups likely pose a threat to critical infrastructure organizations primarily through:

  • Deploying ransomware through which cyber actors remove victim access to data (usually via encryption), potentially causing significant disruption to operations.
  • Conducting DDoS attacks against websites. 
    • In a DDoS attack, the cyber actor generates enough requests to flood and overload the target page and stop it from responding. 
    • DDoS attacks are often accompanied by extortion. 
    • According to industry reporting, some cybercrime groups have recently carried out DDoS attacks against Ukrainian defense organizations, and one group claimed credit for DDoS attack against a U.S. airport the actors perceived as supporting Ukraine (see the Killnet section).

Based on industry and open-source reporting, U.S., Australian, Canadian, New Zealand, and UK cyber authorities assess multiple Russian-aligned cybercrime groups pose a threat to critical infrastructure organizations. These groups include:

  • The CoomingProject
  • Killnet
  • MUMMY SPIDER 
  • SALTY SPIDER
  • SCULLY SPIDER
  • SMOKEY SPIDER
  • WIZARD SPIDER
  • The Xaknet Team

Note: although some cybercrime groups may conduct cyber operations in support of the Russian government, U.S., Australian, Canadian, New Zealand, and UK cyber authorities assess that cyber criminals will most likely continue to operate primarily based on financial motivations, which may include targeting government and critical infrastructure organizations.

The CoomingProject

Overview: the CoomingProject is a criminal group that extorts money from victims by exposing or threatening to expose leaked data. Their data leak site was launched in August 2021.[31] The CoomingProject stated they would support the Russian Government in response to perceived cyberattacks against Russia.[32]

Killnet

Overview: according to open-source reporting, Killnet released a video pledging support to Russia.[33
Victims: Killnet claimed credit for carrying out a DDoS attack against a U.S. airport in March 2022 in response to U.S. materiel support for Ukraine.[34]

MUMMY SPIDER

Overview: MUMMY SPIDER is a cybercrime group that creates, distributes, and operates the Emotet botnet. Emotet is advanced, modular malware that originated as a banking trojan (malware designed to steal information from banking systems but that may also be used to drop additional malware and ransomware). Today Emotet primarily functions as a downloader and distribution service for other cybercrime groups. Emotet has been used to deploy WIZARD SPIDER’s TrickBot, which is often a precursor to ransomware delivery. Emotet has worm-like features that enable rapid spreading in an infected network. 

Victims: according to open sources, Emotet has been used to target industries worldwide, including financial, e-commerce, healthcare, academia, government, and technology organizations’ networks.

Also known as: Gold Crestwood, TA542, TEMP.Mixmaster, UNC3443

Resources: for more information on Emotet, see joint Alert Emotet Malware. For more information on TrickBot, see joint CSA TrickBot Malware

SALTY SPIDER

Overview: SALTY SPIDER is a cybercrime group that develops and operates the Sality botnet. Sality is a polymorphic file infector that was discovered in 2003; since then, it has been replaced by more advanced peer-to-peer (P2P) malware loaders.[35]

Victims: according to industry reporting, in February 2022, SALTY SPIDER conducted DDoS attacks against Ukrainian web forums used to discuss events relating to Russia’s military offensive against the city of Kharkiv.

Also known as: Sality

SCULLY SPIDER

Overview: SCULLY SPIDER is a cybercrime group that operates using a malware-as-a-service model; SCULLY SPIDER maintains command and control infrastructure and sells access to their malware and infrastructure to affiliates, who distribute their own malware.[36][37] SCULLY SPIDER develops and operates the DanaBot botnet, which originated primarily as a banking Trojan but expanded beyond banking in 2021 and has since been used to facilitate access for other types of malware, including TrickBot, DoppelDridex, and Zloader. Like Emotet, Danabot effectively functions as an initial access vector for other malware, which can result in ransomware deployment.

According to industry reporting, recent DDoS activity by the DanaBot botnet suggests SCULLY SPIDER has operated in support of Russia’s military offensive in Ukraine. 

Victims: SCULLY SPIDER affiliates have primarily targeted organizations in the United States, Canada, Germany, United Kingdom, Australia, Italy, Poland, Mexico, and Ukraine.[38] According to industry reporting, in March 2022, Danabot was used in DDoS attacks against multiple Ukrainian government organizations. 

Also known as: Gold Opera

SMOKEY SPIDER

Overview: SMOKEY SPIDER is a cybercrime group that develops Smoke Loader (also known as Smoke Bot), a malicious bot that is used to upload other malware. Smoke Loader has been available since at least 2011, and operates as a malware distribution service for a number of different payloads, including—but not limited to—DanaBot, TrickBot, and Qakbot.

Victims: according to industry reporting, Smoke Loader was observed in March 2022 distributing DanaBot payloads that were subsequently used in DDoS attacks against Ukrainian targets.
Resources: for more information on Smoke Loader, see the MITRE ATT&CK webpage on Smoke Loader.

WIZARD SPIDER

Overview: WIZARD SPIDER is a cybercrime group that develops TrickBot malware and Conti ransomware. Historically, the group has paid a wage to the ransomware deployers (referred to as affiliates), some of whom may then receive a share of the proceeds from a successful ransomware attack. In addition to TrickBot, notable initial access and persistence vectors for affiliated actors include Emotet, Cobalt Strike, spearphishing, and stolen or weak Remote Desktop Protocol (RDP) credentials.

After obtaining access, WIZARD SPIDER affiliated actors have relied on various publicly available and otherwise legitimate tools to facilitate earlier stages of the attack lifecycle before deploying Conti ransomware.

WIZARD SPIDER pledged support to the Russian government and threatened critical infrastructure organizations of countries perceived to carry out cyberattacks or war against the Russian government.[39] They later revised this pledge and threatened to retaliate against perceived attacks against the Russian people.[40]

Victims: Conti victim organizations span across multiple industries, including construction and engineering, legal and professional services, manufacturing, and retail. In addition, WIZARD SPIDER affiliates have deployed Conti ransomware against U.S. healthcare and first responder networks.

Also known as: UNC2727, Gold Ulrick

Resources: for more information on Conti, see joint CSA Conti Ransomware. For more information on TrickBot, see joint CSA TrickBot Malware

The XakNet Team

Overview: XakNet is a Russian-language cyber group that has been active as early as March 2022. According to open-source reporting, the XakNet Team threatened to target Ukrainian organizations in response to perceived DDoS or other attacks against Russia.[41] According to reporting from industry, on March 31, 2022, XakNet released a statement stating they would work “exclusively for the good of [Russia].” According to industry reporting, the XakNet Team may be working with or associated with Killnet actors, who claimed credit for the DDoS attacks against a U.S. airport (see the Killnet section).

Victims: according to industry reporting, in late March 2022, the XakNet Team leaked email contents of a Ukrainian government official. The leak was accompanied by a political statement criticizing the Ukrainian government, suggesting the leak was politically motivated. 

U.S., Australian, Canadian, New Zealand, and UK cyber authorities urge critical infrastructure organizations to prepare for and mitigate potential cyber threats by immediately (1) updating software, (2) enforcing MFA, (3) securing and monitoring RDP and other potentially risky services, and (4) providing end-user awareness and training.

  • Update software, including operating systems, applications, and firmware, on IT network assets. Prioritize patching known exploited vulnerabilities and critical and high vulnerabilities that allow for remote code execution or denial-of-service on internet-facing equipment.
    • Consider using a centralized patch management system. For OT networks, use a risk-based assessment strategy to determine the OT network assets and zones that should participate in the patch management program.  
    • Consider signing up for CISA’s cyber hygiene services, including vulnerability scanning, to help reduce exposure to threats. CISA’s vulnerability scanning service evaluates external network presence by executing continuous scans of public, static IP addresses for accessible services and vulnerabilities.
  • Enforce MFA to the greatest extent possible and require accounts with password logins, including service accounts, to have strong passwords. Do not allow passwords to be used across multiple accounts or stored on a system to which an adversary may have access. As Russian state-sponsored APT actors have demonstrated the ability to exploit default MFA protocols and known vulnerabilities, organizations should review configuration policies to protect against “fail open” and re-enrollment scenarios. For more information, see joint CSA Russian State-Sponsored Cyber Actors Gain Network Access by Exploiting Default Multifactor Authentication Protocols and “PrintNightmare” Vulnerability.
  • If you use RDP and/or other potentially risky services, secure and monitor them closely. RDP exploitation is one of the top initial infection vectors for ransomware, and risky services, including RDP, can allow unauthorized access to your session using an on-path attacker.
    • Limit access to resources over internal networks, especially by restricting RDP and using virtual desktop infrastructure. After assessing risks, if RDP is deemed operationally necessary, restrict the originating sources and require MFA to mitigate credential theft and reuse. If RDP must be available externally, use a virtual private network (VPN) or other means to authenticate and secure the connection before allowing RDP to connect to internal devices. Monitor remote access/RDP logs, enforce account lockouts after a specified number of attempts to block brute force attempts, log RDP login attempts, and disable unused remote access/RDP ports.
    • Ensure devices are properly configured and that security features are enabled. Disable ports and protocols that are not being used for a business purpose (e.g., RDP Transmission Control Protocol Port 3389). 
  • Provide end-user awareness and training to help prevent successful targeted social engineering and spearphishing campaigns. Phishing is one of the top infection vectors for ransomware, and Russian state-sponsored APT actors have conducted successful spearphishing campaigns to gain credentials of target networks.
    • Ensure that employees are aware of potential cyber threats and delivery methods. 
    • Ensure that employees are aware of what to do and whom to contact when they receive a suspected phishing email or suspect a cyber incident.

As part of a longer-term effort, implement network segmentation to separate network segments based on role and functionality. Network segmentation can help prevent the spread of ransomware and threat actor lateral movement by controlling traffic flows between—and access to—various subnetworks.

  • Ensure OT assets are not externally accessible. Ensure strong identity and access management when OT assets needs to be externally accessible.
  • Appropriately implement network segmentation between IT and OT networks. Network segmentation limits the ability of adversaries to pivot to the OT network even if the IT network is compromised. Define a demilitarized zone that eliminates unregulated communication between the IT and OT networks.
  • Organize OT assets into logical zones by considering criticality, consequence, and operational necessity. Define acceptable communication conduits between the zones and deploy security controls to filter network traffic and monitor communications between zones. Prohibit ICS protocols from traversing the IT network.

To further prepare for and mitigate cyber threats from Russian state-sponsored or criminal actors, U.S., Australian, Canadian, New Zealand, and UK cyber authorities encourage critical infrastructure organizations to implement the recommendations listed below.

Preparing for Cyber Incidents

  • Create, maintain, and exercise a cyber incident response and continuity of operations plan. 
    • Ensure the cyber incident response plan contains ransomware- and DDoS-specific annexes. For information on preparing for DDoS attacks, see NCSC-UK guidance on preparing for denial-of-service attacks.
    • Keep hard copies of the incident response plan to ensure responders and network defenders can access the plan if the network has been shut down by ransomware, etc.
  • Maintain offline (i.e., physically disconnected) backups of data. Backup procedures should be conducted on a frequent, regular basis (at a minimum every 90 days). Regularly test backup procedures and ensure that backups are isolated from network connections that could enable the spread of malware.
    • Ensure the backup keys are kept offline as well, to prevent them being encrypted in a ransomware incident.
  • Ensure all backup data is encrypted, immutable (i.e., cannot be altered or deleted), and covers the entire organization’s data infrastructure with a particular focus on key data assets.
  • Develop recovery documentation that includes configuration settings for common devices and critical equipment. Such documentation can enable more efficient recovery following an incident.
  • Identify the attack surface by mapping and accounting all external-facing assets (applications, servers, IP addresses) that are vulnerable to DDoS attacks or other cyber operations.
  • For OT assets/networks:
    • Identify a resilience plan that addresses how to operate if you lose access to—or control of—the IT and/or OT environment.
    • Identify OT and IT network interdependencies and develop workarounds or manual controls to ensure ICS networks can be isolated from IT networks if the connections create risk to the safe and reliable operation of OT processes. Regularly test contingency plans, such as manual controls, so that safety-critical functions can be maintained during a cyber incident. Ensure that the OT network can operate at necessary capacity even if the IT network is compromised.
    • Regularly test manual controls so that critical functions can be kept running if ICS or OT networks need to be taken offline.
    • Implement data backup procedures.
    • Develop recovery documents that include configuration settings for common devices and critical OT equipment. 

Identity and Access Management

  • Require accounts with password logins, including service accounts, to have strong passwords and do not allow passwords to be used across multiple accounts or stored on a system to which an adversary may have access. Consider using a password manager; see NCSC-UK’s Password Manager Buyers Guide for guidance.
  • Implement authentication timeout and lockout features to prevent repeated failed login attempts and successful brute-force attempts.
  • Create a deny list of known compromised credentials and prevent users from using known-compromised passwords.
  • Secure credentials by restricting where accounts and credentials can be used and by using local device credential protection features. Russian state-sponsored APT actors have demonstrated their ability to maintain persistence using compromised credentials.
    • Use virtualizing solutions on modern hardware and software to ensure credentials are securely stored.
    • Ensure storage of clear text passwords in Local Security Authority Subsystem Service (LSASS) memory is disabled. Note: for Windows 8, this is enabled by default. For more information see Microsoft Security Advisory Update to Improve Credentials Protection and Management.
    • Consider disabling or limiting NTLM and WDigest Authentication.
    • Implement Credential Guard for Windows 10 and Server 2016 (refer to Microsoft: Manage Windows Defender Credential Guard for more information). For Windows Server 2012R2, enable Protected Process Light for Local Security Authority (LSA).
    • Minimize the Active Directory (AD) attack surface to reduce malicious ticket-granting activity. Malicious activity such as “Kerberoasting” takes advantage of Kerberos’ Ticket Granting Service (TGS) and can be used to obtain hashed credentials that malicious cyber actors attempt to crack.
  • Audit domain controllers to log successful Kerberos TGS requests and ensure the events are monitored for anomalous activity.  
    • Secure accounts.
    • Enforce the principle of least privilege. Administrator accounts should have the minimum permission necessary to complete their tasks.
    • Ensure there are unique and distinct administrative accounts for each set of administrative tasks.
    • Create non-privileged accounts for privileged users and ensure they use the non-privileged accounts for all non-privileged access (e.g., web browsing, email access).
  • Disable inactive accounts uniformly across the AD, MFA systems, etc.
  • Implement time-based access for privileged accounts. The FBI and CISA observed cybercriminals conducting increasingly impactful attacks against U.S. entities on holidays and weekends in 2021. Threat actors may view holidays and weekends—when offices are normally closed—as attractive timeframes, as there are fewer network defenders and IT support personnel at victim organizations. The just-in-time access method provisions privileged access when needed and can support enforcement of the principle of least privilege (as well as the zero-trust model) by setting network-wide policy to automatically disable admin accounts at the AD level. As needed, individual users can submit requests through an automated process that enables access to a system for a set timeframe. 

Protective Controls and Architecture

  • Identify, detect, and investigate abnormal activity that may indicate lateral movement by a threat actor, ransomware, or other malware. Use network monitoring tools and host-based logs and monitoring tools, such as an endpoint detection and response (EDR) tool. EDR tools are particularly useful for detecting lateral connections as they have insight into common and uncommon network connections for each host.
  • Implement a firewall and configure it to block Domain Name System (DNS) responses from outside the enterprise network or drop Internet Control Message Protocol (ICMP) packets. Review which admin services need to be accessible externally and allow those explicitly, blocking all others by default.
    • U.S. Defense Industrial Base organizations may sign up for the NSA Cybersecurity Collaboration Center’s Protective Domain Name System (PDNS) services.
  • Enable web application firewalls to mitigate application-level DDoS attacks. 
  • Implement a multi-content delivery network (CDN) solution. This will minimize the threat of DDoS attacks by distributing and balancing web traffic across a network.

Vulnerability and Configuration Management

  • Use an antivirus programs that uses heuristics and reputational ratings to check a file’s prevalence and digital signature prior to execution. Note: organizations should assess the risks inherent in their software supply chain (including its security/antivirus software supply chain) in light of the existing threat landscape.
    • Set antivirus/antimalware programs to conduct regular scans of IT network assets using up-to-date signatures. 
    • Use a risk-based asset inventory strategy to determine how OT network assets are identified and evaluated for the presence of malware.
  • Implement rigorous configuration management programs. Ensure the programs can track and mitigate emerging threats. Review system configurations for misconfigurations and security weaknesses.
  • Disable all unnecessary ports and protocols.
    • Review network security device logs and determine whether to shut off unnecessary ports and protocols. Monitor common ports and protocols for command and control activity.
    • Turn off or disable any unnecessary services (e.g., PowerShell) or functionality within devices.
  • Identify business-to-business VPNs and block high-risk protocols.
  • Ensure OT hardware is in read-only mode.
  • Enable strong spam filters.
    • Enable strong spam filters to prevent phishing emails from reaching end users.
    • Filter emails containing executable files to prevent them from reaching end users.
    • Implement a user training program to discourage users from visiting malicious websites or opening malicious attachments.
  • Restrict Server Message Block (SMB) Protocol within the network to only access servers that are necessary and remove or disable outdated versions of SMB (i.e., SMB version 1). Threat actors use SMB to propagate malware across organizations.
  • Review the security posture of third-party vendors and those interconnected with your organization. Ensure all connections between third-party vendors and outside software or hardware are monitored and reviewed for suspicious activity.
  • Implement listing policies for applications and remote access that only allow systems to execute known and permitted programs under an established security policy.
  • Open document readers in protected viewing modes to help prevent active content from running.

Responding to Cyber Incidents

U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities urge network defenders of critical infrastructure organizations to exercise due diligence in identifying indicators of malicious activity. Organizations detecting potential APT or ransomware activity in their IT or OT networks should:

  1. Immediately isolate affected systems.
  2. For DDoS attacks:
    1. Identify the source address originating the attack via the SIEM or logging service. If the attack is originating from a single pool of IP addresses, block IP traffic from suspected IPs via access control lists or by contacting your internet service provider (ISP).
    2. Enable firewall rate limiting to restrict the amount of IP traffic coming in from suspected IP addresses
    3. Notify your ISP and enable remote triggered blackhole (RTBH).
  3. Secure backups. Ensure your backup data is offline and secure. If possible, scan your backup data with an antivirus program to ensure it is free of malware.
  4. Collect and review relevant logs, data, and artifacts.
  5. Consider soliciting support from a third-party IT organization to provide subject matter expertise, ensure the actor is eradicated from the network, and avoid residual issues that could enable follow-on exploitation.
  6. Report incidents to appropriate cyber and law enforcement authorities:
  • U.S organizations: share information about incidents and anomalous activity to CISA’s 24/7 Operations Center at [email protected] or (888) 282-0870 and/or the FBI via your local FBI field office or the FBI’s 24/7 CyWatch at (855) 292-3937 or [email protected]. For ransomware incidents, organizations can also report to the U.S. Secret Service via a U.S. Secret Service Field Office
  • Australian organizations: if you have questions about this advice or have indications that your environment has been compromised, call the ACSC at 1300 CYBER1 (1300 292 371). To report an incident see cyber.gov.au/acsc/report.
  • Canadian organizations: report incidents by emailing CCCS at [email protected].
  • New Zealand organizations: if your organization requires assistance from the National Cyber Security Centre, contact them directly via telephone at (04) 498-7654 or via email at [email protected].
  • UK organizations: report a significant cybersecurity incident at ncsc.gov.uk/report-an-incident (monitored 24 hours) or, for urgent assistance, call 03000 200 973.

For additional guidance on responding to a ransomware incident, see the CISA-Multi-State Information Sharing and Analysis Center (MS-ISAC) Joint Ransomware Guide.

See the joint advisory from Australia, Canada, New Zealand, the United Kingdom, and the United States on Technical Approaches to Uncovering and Remediating Malicious Activity for guidance on hunting or investigating a network, and for common mistakes in incident handling.

Additionally, CISA, the FBI, and NSA encourage U.S. critical infrastructure owners and operators to see CISA’s Federal Government Cybersecurity Incident and Vulnerability Response Playbooks. Although tailored to federal civilian branch agencies, these playbooks provide operational procedures for planning and conducting cybersecurity incident and vulnerability response activities and detail each step for both incident and vulnerability response.  

Note: U.S., Australian, Canadian, New Zealand, and UK cyber authorities strongly discourage paying a ransom to criminal actors. Paying a ransom may embolden adversaries to target additional organizations, encourage other criminal actors to engage in the distribution of ransomware, and/or fund illicit activities. Paying the ransom does not guarantee that a victim’s files will be recovered.

RESOURCES

DISCLAIMER

The information you have accessed or received is being provided “as is” for informational purposes only. CISA, NSA, FBI, ACSC, CCCS, NZ NCSC, NCSC-UK, and the UK National Crime Agency (NCA) do not endorse any commercial product or service, including any subjects of analysis. Any reference to specific commercial products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring.

TRADEMARK RECOGNITION

MITRE and ATT&CK are registered trademarks of The MITRE Corporation. Kubernetes is a registered trademark of The Linux Foundation.

PURPOSE 

This document was developed by U.S., Australian, Canadian, New Zealand, and UK cybersecurity authorities in furtherance of their respective cybersecurity missions, including their responsibilities to develop and issue cybersecurity specifications and mitigations.

REFERENCES

[1] Cybersecurity and Infrastructure Security Agency
[2] Federal Bureau of Investigation
[3] National Security Agency
[4] Australian Cyber Security Centre
[5] Canadian Centre for Cyber Security
[6] New Zealand’s National Cyber Security Centre
[7] United Kingdom’s National Cyber Security Centre
[8] United Kingdom’s National Crime Agency
[9] U.S. DOJ Press Release: U.S. Charges Russian FSB Officers and Their Criminal Conspirators for Hacking Yahoo and Millions of Email Accounts
[10] U.S. DOJ Press Release: Four Russian Government Employees Charged in Two Historical Hacking Campaigns Targeting Critical Infrastructure Worldwide
[11] CrowdStrike Blog: Early Bird Catches the Wormhole: Observations from the StellarParticle Campaign
[12] U.S. White House Statement: FACT SHEET: Imposing Costs for Harmful Foreign Activities by the Russian
[
13] Government of Canada Statement on SolarWinds Cyber Compromise
[14] UK Government Press Release: Russia: UK and US expose global campaign of malign activity by Russian intelligence services
[15] MITRE ATT&CK: APT29
[
16] Joint CSA Russian GRU 85th GTsSS Deploys Previously Undisclosed Drovorub Malware
[17] Joint CSA Russian GRU Conducting Global Brute Force Campaign to Compromise Enterprise and Cloud Environments
[18] MITRE ATT&CK APT28
[19] Joint CSA New Sandworm Malware Cyclops Blink Replaces VPNFilter
[20] UK Government Press Release: UK condemns Russia’s GRU over Georgia cyber-attacks
[21] U.S. Department of State, Press Statement: The United States Condemns Russian Cyber Attack Against the Country of Georgia
[22] Government of Canada CSE Statement on Malicious Russian Cyber Activity Targeting Georgia
[23] UK Government Press Release: UK condemns Russia’s GRU over Georgia cyber-attacks
[24] MITRE ATT&CK The Sandworm Team
[25] U.S. Department of the Treasury Press Release: Treasury Sanctions Russian Government Research Institution Connected to the Triton Malware
[26] UK Government Press Release: UK exposes Russian spy agency behind cyber incident
[27] U.S. DOJ Press Release: Four Russian Government Employees Charged in Two Historical Hacking Campaigns Targeting Critical Infrastructure Worldwide
[28] MITRE ATT&CK TEMP.Veles
[29] NSA and NCSC-UK Cybersecurity Advisory Turla Group Exploits Iranian APT To Expand Coverage Of Victims
[30] CrowdStrike Adversary Profile: VENEMOUS BEAR
[31] KELA Cybersecurity Intelligence Center: Ain’t No Actor Trustworthy Enough: The importance of validating sources
[32] Twitter: Valery Marchive Status, Feb. 25, 2022 1:41 PM
[33] The Record by Recorded Future: Russia or Ukraine: Hacking Groups Take Sides
[34] Twitter: CyberKnow Status, March 29, 2022, 7:54 AM
[35] CrowdStrike Blog: Who is Salty Spider (Sality)?
[36] Proofpoint Blog: New Year, New Version of DanaBot
[37] Zscaler Blog: Spike in DanaBot Malware Activity
[38] Proofpoint Blog: New Year, New Version of DanaBot
[39] The Record by Recorded Future: Russia or Ukraine: Hacking Groups Take Sides
[40] TechTarget: Conti ransomware gang backs Russia, threatens US
[41] The Record by Recorded Future: Russia or Ukraine: Hacking Groups Take Sides

ACKNOWLEDGEMENTS

The U.S., Australian, Canadian, New Zealand, and UK cyber authorities would like to thank CrowdStrike, Google, LookingGlass Cyber, Mandiant, Microsoft, and Secureworks for their contributions to this CSA.

Source…