CISA Advisories

View CSAF Summary ABB became aware of vulnerability in the products versions listed as affected in the advisory. The ABB S+ Engineering product versions are affected by vulnerabilities in PostgreSQL version 13.11 and earlier versions. If an attacker gains access to a site’s S+ Client Server network, they could exploit such vulnerabilities by executing arbitrary code and potentially compromising the entire system. The following versions of ABB Ability Symphony Plus Engineering are affected: Ability Symphony Plus 2.2, 2.3, 2.3_RU1, 2.3_RU2, 2.3_RU3, 2.4, 2.4_SP1, 2.4_SP2, 2.4_SP2_RU1 CVSS Vendor Equipment Vulnerabilities v3 8.8 ABB ABB Ability Symphony Plus Engineering Integer Overflow or Wraparound, Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection'), Time-of-check Time-of-use (TOCTOU) Race Condition, Privilege Dropping / Lowering Errors Background Critical Infrastructure Sectors: Chemical, Critical Manufacturing, Energy, Water and Wastewater Countries/Areas Deployed: Worldwide Company Headquarters Location: Switzerland Vulnerabilities Expand All + CVE-2023-5869 An attacker running as an authenticated PostgreSQL user can provide crafted data and trigger the integer overflow due to such missing overflow check. This can enable the execution of arbitrary code in the system. View CVE Details Affected Products ABB Ability Symphony Plus Engineering Vendor: ABB Product Version: ABB Ability Symphony Plus S+ Engineering 2.2, ABB Ability Symphony Plus S+ Engineering 2.3, ABB Ability Symphony Plus S+ Engineering 2.3 RU1, ABB Ability Symphony Plus S+ Engineering 2.3 RU2, ABB Ability Symphony Plus S+ Engineering 2.3 RU3, ABB Ability Symphony Plus S+ Engineering 2.4, ABB Ability Symphony Plus S+ Engineering 2.4 SP1, ABB Ability Symphony Plus S+ Engineering 2.4 SP2 Product Status: fixed, known_affected Remediations Vendor fix ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - Systems using S+ Engineering 2.2 through 2.4 SP2 should upgrade to S+ Engineering 2.4 SP2 RU1 (re-leased in December 2024) or later. - End users who are unable to install one of these updates should immediately look to implement the Mitigation and Workarounds listed below as this will restrict or prevent an attacker’s ability to com-promise the system. ABB recommends that customers apply the update at the earliest convenience. Mitigation Any exploit of these vulnerabilities would require that the attacker has access to the site’s S+ client/server network. Following ABB’s recommended security practices, including network architecture and perimeter firewall, are mitigating factors in preventing external access to the S+ client/server net-work. Refer to section “General security recommendations” for further advise on how to keep your system secure. Workaround No workarounds are available. Assess the installation specific risk based on this advisory. Use the recommendations described under “Mitigating factors” or “Recommended immediate actions”. Relevant CWE: CWE-190 Integer Overflow or Wraparound Metrics CVSS Version Base Score Base Severity Vector String 3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C CVE-2023-39417 If an administrator has installed Extension scripts and specific data is used inside a quoting con-struct, an attacker having proper PostgreSQL privileges can execute arbitrary code in the system as the administrator. View CVE Details Affected Products ABB Ability Symphony Plus Engineering Vendor: ABB Product Version: ABB Ability Symphony Plus S+ Engineering 2.2, ABB Ability Symphony Plus S+ Engineering 2.3, ABB Ability Symphony Plus S+ Engineering 2.3 RU1, ABB Ability Symphony Plus S+ Engineering 2.3 RU2, ABB Ability Symphony Plus S+ Engineering 2.3 RU3, ABB Ability Symphony Plus S+ Engineering 2.4, ABB Ability Symphony Plus S+ Engineering 2.4 SP1, ABB Ability Symphony Plus S+ Engineering 2.4 SP2 Product Status: fixed, known_affected Remediations Vendor fix ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - Systems using S+ Engineering 2.2 through 2.4 SP2 should upgrade to S+ Engineering 2.4 SP2 RU1 (re-leased in December 2024) or later. - End users who are unable to install one of these updates should immediately look to implement the Mitigation and Workarounds listed below as this will restrict or prevent an attacker’s ability to com-promise the system. ABB recommends that customers apply the update at the earliest convenience. Mitigation Any exploit of these vulnerabilities would require that the attacker has access to the site’s S+ client/server network. Following ABB’s recommended security practices, including network architecture and perimeter firewall, are mitigating factors in preventing external access to the S+ client/server net-work. Refer to section “General security recommendations” for further advise on how to keep your system secure. Workaround No workarounds are available. Assess the installation specific risk based on this advisory. Use the recommendations described under “Mitigating factors” or “Recommended immediate actions”. Relevant CWE: CWE-89 Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') Metrics CVSS Version Base Score Base Severity Vector String 3.1 7.5 HIGH CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C CVE-2024-7348 A ‘time-of-check time-of-use’ (TOCTOU) race condition in a PostgreSQL can allow an attacker to easily execute arbitrary SQL functions by leveraging a PostgreSQL utility often executed with high privileges. View CVE Details Affected Products ABB Ability Symphony Plus Engineering Vendor: ABB Product Version: ABB Ability Symphony Plus S+ Engineering 2.2, ABB Ability Symphony Plus S+ Engineering 2.3, ABB Ability Symphony Plus S+ Engineering 2.3 RU1, ABB Ability Symphony Plus S+ Engineering 2.3 RU2, ABB Ability Symphony Plus S+ Engineering 2.3 RU3, ABB Ability Symphony Plus S+ Engineering 2.4, ABB Ability Symphony Plus S+ Engineering 2.4 SP1, ABB Ability Symphony Plus S+ Engineering 2.4 SP2 Product Status: fixed, known_affected Remediations Vendor fix ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - Systems using S+ Engineering 2.2 through 2.4 SP2 should upgrade to S+ Engineering 2.4 SP2 RU1 (re-leased in December 2024) or later. - End users who are unable to install one of these updates should immediately look to implement the Mitigation and Workarounds listed below as this will restrict or prevent an attacker’s ability to com-promise the system. ABB recommends that customers apply the update at the earliest convenience. Mitigation Any exploit of these vulnerabilities would require that the attacker has access to the site’s S+ client/server network. Following ABB’s recommended security practices, including network architecture and perimeter firewall, are mitigating factors in preventing external access to the S+ client/server net-work. Refer to section “General security recommendations” for further advise on how to keep your system secure. Workaround No workarounds are available. Assess the installation specific risk based on this advisory. Use the recommendations described under “Mitigating factors” or “Recommended immediate actions”. Relevant CWE: CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition Metrics CVSS Version Base Score Base Severity Vector String 3.1 8.8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C CVE-2024-0985 An attacker can provide untrusted materialized views and lure a high privileged authorized user to inadvertently execute arbitrary SQL functions by refreshing the attacker's materialized view. View CVE Details Affected Products ABB Ability Symphony Plus Engineering Vendor: ABB Product Version: ABB Ability Symphony Plus S+ Engineering 2.2, ABB Ability Symphony Plus S+ Engineering 2.3, ABB Ability Symphony Plus S+ Engineering 2.3 RU1, ABB Ability Symphony Plus S+ Engineering 2.3 RU2, ABB Ability Symphony Plus S+ Engineering 2.3 RU3, ABB Ability Symphony Plus S+ Engineering 2.4, ABB Ability Symphony Plus S+ Engineering 2.4 SP1, ABB Ability Symphony Plus S+ Engineering 2.4 SP2 Product Status: fixed, known_affected Remediations Vendor fix ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - Systems using S+ Engineering 2.2 through 2.4 SP2 should upgrade to S+ Engineering 2.4 SP2 RU1 (re-leased in December 2024) or later. - End users who are unable to install one of these updates should immediately look to implement the Mitigation and Workarounds listed below as this will restrict or prevent an attacker’s ability to com-promise the system. ABB recommends that customers apply the update at the earliest convenience. Mitigation Any exploit of these vulnerabilities would require that the attacker has access to the site’s S+ client/server network. Following ABB’s recommended security practices, including network architecture and perimeter firewall, are mitigating factors in preventing external access to the S+ client/server net-work. Refer to section “General security recommendations” for further advise on how to keep your system secure. Workaround No workarounds are available. Assess the installation specific risk based on this advisory. Use the recommendations described under “Mitigating factors” or “Recommended immediate actions”. Relevant CWE: CWE-271 Privilege Dropping / Lowering Errors Metrics CVSS Version Base Score Base Severity Vector String 3.1 8 HIGH CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:F/RL:U/RC:C Acknowledgments ABB Global reported these vulnerabilities to CISA. Notice The information in this document is subject to change without notice, and should not be construed as a commitment by ABB. ABB provides no warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, for the information contained in this document, and assumes no responsibility for any errors that may appear in this document. In no event shall ABB or any of its suppliers be liable for direct, indirect, special, incidental or consequential damages of any nature or kind arising from the use of this document, or from the use of any hardware or software described in this document, even if ABB or its suppliers have been advised of the possibility of such damages. This document and parts hereof must not be reproduced or copied without written permission from ABB, and the contents hereof must not be imparted to a third party nor used for any unauthorized purpose. All rights to registrations and trademarks reside with their respective owners. Frequently Asked Questions What is the scope of the vulnerability? - An attacker who successfully exploited these vulnerabilities could insert and run arbitrary code in the S+ system. What causes the vulnerability? - It is caused by several vulnerabilities in the PostgreSQL version 13.11 and earlier versions component used by the S+ Engineering product (see Affected products). What might an attacker use the vulnerability to do? - An attacker who successfully accessed the site’s S+ client/server network could cause a denial-of-service situation, corruptions of data or unauthorized disclosure of information. How could an attacker exploit the vulnerability? - To exploit the PostgreSQL vulnerabilities (see Vulnerability severity and details), an attacker should successfully access to the site’s S+ client/server network, remotely (through a wrongly configured or penetrated firewall) or even compromising a local machine and then accessing to PostgreSQL. Recommended practices help mitigate such attacks, see section Mitigating Factors above. Could the vulnerability be exploited remotely? - Yes, see the above How could an attacker exploit the vulnerability? Recommended practices include that process control systems are physically protected, have no direct connections to the Internet, and are separated from other networks by means of a firewall system that has a minimal number of ports exposed. Can functional safety be affected by an exploit of this vulnerability? - Functional safety systems are not affected by these vulnerabilities What does the update do? - The S+ Engineering update removes the vulnerability by installing a secure updated PostgreSQL version. When this security advisory was issued, had this vulnerability been publicly disclosed? - Yes, PostgreSQL 13.11 vulnerabilities have been publicly disclosed. When this security advisory was issued, had ABB received any reports that this vulnerability was being exploited? - No, ABB had not received any information indicating that S+ Engineering had been exploited when this security advisory was originally issued. Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the exploitation risk of this vulnerability. Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolate them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most recent version available. Also recognize VPN is only as secure as its connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. Advisory Conversion Disclaimer This ICSA is a verbatim republication of ABB PSIRT 7PAA017341 from a direct conversion of the vendor's Common Security Advisory Framework (CSAF) advisory. This is republished to CISA's website as a means of increasing visibility and is provided "as-is" for informational purposes only. CISA is not responsible for the editorial or technical accuracy of republished advisories and provides no warranties of any kind regarding any information contained within this advisory. Further, CISA does not endorse any commercial product or service. Please contact ABB PSIRT directly for any questions regarding this advisory. Revision History Initial Release Date: 2026-04-13 Date Revision Summary 2026-04-13 1 Initial version. 2026-04-30 2 Initial CISA Republication of ABB PSIRT 7PAA017341 advisory Legal Notice and Terms of Use

View CSAF Summary Successful exploitation of this vulnerability could allow an attacker to send specially crafted messages to the system node resulting in execution of arbitrary code. The following versions of ABB PCM600 are affected: PCM600 >=1.5|<=2.13 CVSS Vendor Equipment Vulnerabilities v3 4.4 ABB ABB PCM600 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') Background Critical Infrastructure Sectors: Critical Manufacturing Countries/Areas Deployed: Worldwide Company Headquarters Location: Switzerland Vulnerabilities Expand All + CVE-2018-1002208 A vulnerability exists in the SharpZip.dll included in the product versions listed above. An attacker could exploit vulnerability by providing a specially crafted message to the system node, causing insertion, and running of arbitrary code. View CVE Details Affected Products ABB PCM600 Vendor: ABB Product Version: ABB PCM600: >=1.5|<=2.13 Product Status: known_affected Remediations Vendor fix The problem is corrected in the following product version: ABB Protection and control IED manager PCM600 version 2.14. ABB recommends that customers apply the update at earliest convenience. Vendor fix Note: RE_630 protection relays are not compatible with PCM600 version 2.14. When using earlier PCM600 versions with RE_630, the known vulnerability must be mitigated through system-level defenses. For mitigation guidance, refer to the General Security Recommendations. Vendor fix The following product versions have been fixed: Protection and Control IED manager PCM600 2.14 is a fixed version for CVE-2018-1002208 Mitigation For more information see the associated ABB PSIRT security advisory 2NGA002813 ABB CYBERSECURITY ADVISORY - PDF version (https://search.abb.com/library/Download.aspx?DocumentID=2NGA002813&LanguageCode=en&DocumentPartId=pdf&Action=Launch), ABB CYBERSECURITY ADVISORY - CSAF version (https://psirt.abb.com/csaf/2025/2nga002813.json). https://search.abb.com/library/Download.aspx?DocumentID=2NGA002813&LanguageCode=en&DocumentPartId=pdf&Action=Launch Mitigation For more information see the associated ABB PSIRT security advisory 2NGA002813 ABB CYBERSECURITY ADVISORY - PDF version (https://search.abb.com/library/Download.aspx?DocumentID=2NGA002813&LanguageCode=en&DocumentPartId=pdf&Action=Launch), ABB CYBERSECURITY ADVISORY - CSAF version (https://psirt.abb.com/csaf/2025/2nga002813.json). https://psirt.abb.com/csaf/2025/2nga002813.json Relevant CWE: CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') Metrics CVSS Version Base Score Base Severity Vector String 3.1 4.4 MEDIUM CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N Acknowledgments ABB PSIRT reported this vulnerability to CISA Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolating them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs). Recognize VPNs may have vulnerabilities, should be updated to the most recent version available, and are only as secure as the connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. CISA also recommends users take the following measures to protect themselves from social engineering attacks: Do not click web links or open attachments in unsolicited email messages. Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams. Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks. No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. This vulnerability is not exploitable remotely. This vulnerability has a high attack complexity. Revision History Initial Release Date: 2026-04-30 Date Revision Summary 2026-04-30 1 Initial Republication of ABB PSIRT 2NGA002813 Legal Notice and Terms of Use

CISA has added one new vulnerability to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2026-41940 WebPros cPanel & WHM and WP2 (WordPress Squared) Missing Authentication for Critical Function Vulnerability This type of vulnerability is a frequent attack vector for malicious cyber actors and poses significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information. Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of KEV Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the specified criteria.

View CSAF Summary This vulnerability was privately reported relating to ABB’s implementation of the IEC 61850 communication stack for MMS client applications used in some Automation control system products. Note: IEC 61850 communication typically supports MMS and GOOSE protocols. Some ABB products support both, others only MMS (e.g. S+ Operations and PM 877). In any case, GOOSE communication is not impacted by this reported vulnerability. If an attacker gains access to a site’s IEC 61850 network, then exploiting this vulnerability will result in a device fault (PM 877, CI850 and CI868 modules) and will require a manual restart. If this attack is directed at a S+ Operations node running IEC 61850 connectivity, this will result in a crash in the IEC 61850 communication driver which, if continued a repeating basis, will also result in a denial-of-service situation. Note that this does not have an impact on the overall availability and functionality of the S+ Operations node, only the IEC 61850 communication function. The System 800xA IEC61850 Connect is not affected. The following versions of ABB System 800xA, Symphony Plus IEC 61850 are affected: AC800M Product line (System 800xA) CI868 Symphony Plus SD Series CI850 Symphony Plus MR (Melody Rack) PM 877 S+ Operations Firmware <=6.0.0303.0, <=6.1.0031.0 , <=6.1.1004.0 , <=6.1.1202.0 , <=6.2.0006.0 , 6.1.1-3, 7.0, A_0, A_1, A_2.003, A_3.005, A_4.001, B_0.005, C_0, >=3.10|<=3.52, 3.53, 3.3, 2.3, 2.2, 2.1, 3.4 () CVSS Vendor Equipment Vulnerabilities v3 6.5 ABB ABB System 800xA, Symphony Plus IEC 61850 Improper Validation of Specified Quantity in Input Background Critical Infrastructure Sectors: Chemical, Critical Manufacturing, Energy, Water and Wastewater Countries/Areas Deployed: Worldwide Company Headquarters Location: Switzerland Vulnerabilities Expand All + CVE-2025-3756 A vulnerability exists in the command handling of the IEC 61850 communication stack included in the product revisions listed above. An attacker with access to IEC 61850 networks could exploit the vulnerability by using a specially crafted 61850 packet, forcing the communication interfaces of the PM 877, CI850 and CI868 modules into fault mode or causing unavailability of the S+ Operations 61850 connectivity, resulting in a denial-of-service situation. The System 800xA IEC61850 Connect is not affected. Note: This vulnerability does not impact on the overall availability and functionality of the S+ Operations node, only the 61850 communication function. View CVE Details Affected Products ABB System 800xA, Symphony Plus IEC 61850 Vendor: ABB Product Version: Product Status: fixed, known_affected Remediations Vendor fix ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - CI868 (for AC 800M) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in 6.1.1 and 7.0 tracks for 800xA. AC 800M 6.1.1-3 is planned for Q2 2027, AC 800M 7.0 has been released in December 2025. - CI850 (for Symphony Plus SD Series) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in version C_0 or later (planned Q2 2026). - PM 877 (Symphony Plus MR) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected with firmware version 3.53 or later (planned Q1 2026). - S+ Operations Versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in version 3.4 or later (released in January 2026). ABB recommends customers apply updates, as they become available, at their earliest convenience. It is also advisable to review the Mitigating Factors, Workarounds and General security recommendations sections for additional actions which may help reduce overall risk. Mitigation The vulnerabilities announced in this Advisory for ABB Process Automation products require that an attacker has access to the system network and hosts which are generally expected to be protected. Process Control and IEC 61850 networks are NOT recommended to be exposed directly to Internet connections. If these networks are not properly isolated, then connected components may be remotely exploitable as described in this advisory. To exploit the vulnerability, an attacker with remote network access can send a specially crafted packet to the PM 877, CI850 and CI868 modules which causes the fault of these devices. S+ Operations only implements 61850 client services and therefore are not intended to listen to in-coming connection requests. However, if a specially crafted message is sent anyway, it can still cause the 61850-communication driver to crash. The usage of a perimeter firewall to allow legitimate client communications is an effective mitigation. Refer to section “General security recommendations” for further advise on how to keep your system secure. Workaround No workarounds are available. Assess the installation specific risk based on this advisory. Use the recommendations described under “Mitigating factors” or “Recommended immediate actions”. Relevant CWE: CWE-1284 Improper Validation of Specified Quantity in Input Metrics CVSS Version Base Score Base Severity Vector String 3.1 6.5 MEDIUM CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Acknowledgments Hitachi Energy reported this vulnerability to ABB Global. ABB Global reported this vulnerability to CISA. Notice The information in this document is subject to change without notice, and should not be construed as a commitment by ABB. ABB provides no warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, for the information contained in this document, and assumes no responsibility for any errors that may appear in this document. In no event shall ABB or any of its suppliers be liable for direct, indirect, special, incidental or consequential damages of any nature or kind arising from the use of this document, or from the use of any hardware or software described in this document, even if ABB or its suppliers have been advised of the possibility of such damages. This document and parts hereof must not be reproduced or copied without written permission from ABB, and the contents hereof must not be imparted to a third party nor used for any unauthorized purpose. All rights to registrations and trademarks reside with their respective owners. Frequently Asked Questions What is the scope of the vulnerability? - An attacker having access to the IEC 61850 network can force the ABB hardware devices to go to ‘fault’ state by sending a specially crafted 61850 packet. This will result in a denial-of-service situation affecting the primary functionality of the listed devices and requiring a manual reset. In the same way this vulnerability can cause the unavailability of the S+ Operations 61850 connectivity, if continued on a repeating basis (but not the whole S+ Operations node). The System 800xA IEC61850 Connect is not affected. What causes the vulnerability? - The vulnerability is caused by a weakness in the message processing in the IEC 61850 communication stack. What is CI868? - CI868 is a module used in AC800M product line (System 800xA) for IEC 61850 communication. What is CI850? - CI868 is a module used in Symphony Plus SD Series product line for IEC 61850 communication. What is PM 877? - PM 877 is a controller used in Symphony Plus MR (Melody Rack) product line for IEC 61850 communication. What is S+ Operations? - S+ Operations is the Human Machine Interface for supervision and control of Symphony based control or SCADA systems. It is a module used in AC800M product line (System 800xA) for IEC 61850 communication. What might an attacker use the vulnerability to do? - An attacker with access to IEC 61850 networks could exploit the vulnerability by sending a specially crafted 61850 packet to the S+ products, forcing the Communication Interfaces to fault modes or causing unavailability of the S+ Operations 61850 connectivity, resulting in a denial-of-service situation. How could an attacker exploit the vulnerability? - An attacker could try to exploit the vulnerability by creating a specially crafted message and sending the message to an affected system node. This would require that the attacker has access to the system network, by connecting to the network either directly or through a wrongly configured or penetrated firewall, or that he installs malicious software on a system node or otherwise infects the net-work with malicious software. Recommended practices help mitigate such attacks, see section Mitigating Factors. Could the vulnerability be exploited remotely? - Yes, an attacker who has network access to an affected system node could exploit this vulnerability. Recommended practices include that process control systems are physically protected, have no direct connections to the Internet, and are separated from other networks by means of a firewall system that has a minimal number of ports exposed. Can functional safety be affected by an exploit of this vulnerability? - Functional safety systems are not affected by these vulnerabilities. What does the update do? - The update removes the vulnerability by modifying the way that the IEC 61850 stack, used by the ABB Process Automation Products described above, manages 61850 incoming messages. When this security advisory was issued, had this vulnerability been publicly disclosed? - No, ABB received information about this vulnerability through responsible disclosure. When this security advisory was issued, had ABB received any reports that this vulnerability was being exploited? - No, ABB had not received any information indicating that this vulnerability had been exploited when this security advisory was originally issued. Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the exploitation risk of these vulnerabilities. Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolate them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most recent version available. Also recognize VPN is only as secure as its connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. Advisory Conversion Disclaimer This ICSA is a verbatim republication of ABB PSIRT 7PAA020125 from a direct conversion of the vendor's Common Security Advisory Framework (CSAF) advisory. This is republished to CISA's website as a means of increasing visibility and is provided "as-is" for informational purposes only. CISA is not responsible for the editorial or technical accuracy of republished advisories and provides no warranties of any kind regarding any information contained within this advisory. Further, CISA does not endorse any commercial product or service. Please contact ABB PSIRT directly for any questions regarding this advisory. Revision History Initial Release Date: 2026-04-13 Date Revision Summary 2026-04-13 1 Initial version. 2026-04-30 2 Initial CISA Republication of ABB PSIRT 7PAA020125 advisory Legal Notice and Terms of Use

View CSAF Summary Successful exploitation of this vulnerability could allow an attacker to send a specially crafted message to the system node allowing the attacker to install and run arbitrary code, uninstall applications, and modify the configuration of installed applications. The following versions of ABB Edgenius Management Portal are affected: Edgenius Management Portal 3.2.0.0|3.2.1.1 CVSS Vendor Equipment Vulnerabilities v3 9.6 ABB ABB Edgenius Management Portal Authentication Bypass Using an Alternate Path or Channel Background Critical Infrastructure Sectors: Critical Manufacturing, Information Technology Countries/Areas Deployed: Worldwide Company Headquarters Location: Switzerland Vulnerabilities Expand All + CVE-2025-10571 The Edgenius Management Portal in the affected product versions contains a vulnerability that allows authentication to be bypassed. An attacker could exploit the vulnerability by sending a specially crafted message to the system node allowing the attacker to install and run arbitrary code, uninstall in-stalled applications and modify the configuration of installed applications. View CVE Details Affected Products ABB Edgenius Management Portal Vendor: ABB Product Version: ABB Edgenius Management Portal: 3.2.0.0|3.2.1.1 Product Status: known_affected Remediations Vendor fix ABB has prepared an update to fix this vulnerability included in the latest Roll-Up, ABB Ability Edgenius version 3.2.2.0. ABB advises customers to upgrade as soon as possible. Until the upgrade is applied, ABB advises customers to disable the Edgenius Management Portal to mitigate the vulnerability. Vendor fix All affected products: Exploitation requires an attacker to have gained access to the network where Edgenius has been deployed, and while the Edgenius Management Portal is running. Refer to section "General security recommendations" for further advise on how to keep your system secure. Mitigation All affected products: Workarounds are specific measures that a user can take to help block an attack, for example, temporarily disabling the vulnerable feature may remove the exposure with well-known impact on functionality. ABB has tested the following workaround. Mitigation The following product versions have been fixed: Ability Edgenius 3.2.2.0 is a fixed version for CVE-2025-10571 Mitigation For more information see the associated ABB PSIRT security advisory 7PAA022088 ABB CYBERSECURITY ADVISORY - PDF version (https://search.abb.com/library/Download.aspx?DocumentID=7PAA022088&LanguageCode=en&DocumentPartId=&Action=Launch), ABB CYBERSECURITY ADVISORY - CSAF version (https://psirt.abb.com/csaf/2025/7paa022088.json). https://search.abb.com/library/Download.aspx?DocumentID=7PAA022088&LanguageCode=en&DocumentPartId=&Action=Launch Mitigation For more information see the associated ABB PSIRT security advisory 7PAA022088 ABB CYBERSECURITY ADVISORY - PDF version (https://search.abb.com/library/Download.aspx?DocumentID=7PAA022088&LanguageCode=en&DocumentPartId=&Action=Launch), ABB CYBERSECURITY ADVISORY - CSAF version (https://psirt.abb.com/csaf/2025/7paa022088.json). https://psirt.abb.com/csaf/2025/7paa022088.json Relevant CWE: CWE-288 Authentication Bypass Using an Alternate Path or Channel Metrics CVSS Version Base Score Base Severity Vector String 3.1 9.6 CRITICAL CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Acknowledgments ABB PSIRT reported this vulnerability to CISA Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolating them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs). Recognize VPNs may have vulnerabilities, should be updated to the most recent version available, and are only as secure as the connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. CISA also recommends users take the following measures to protect themselves from social engineering attacks: Do not click web links or open attachments in unsolicited email messages. Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams. Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks. No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. This vulnerability is not exploitable remotely. Revision History Initial Release Date: 2026-04-30 Date Revision Summary 2026-04-30 1 Initial Republication of ABB PSIRT 7PAA022088 Legal Notice and Terms of Use

Adapting Zero Trust Principles to Operational Technology CISA, in coordination with the Department of War, Department of Energy, Federal Bureau of Investigation, and Department of State, released Adapting Zero Trust Principles to Operational Technology, joint guidance for organizations applying zero trust (ZT) principles to operational technology (OT). Zero trust is a modern, adaptive approach to cybersecurity that eliminates implicit trust and requires continuously validating access based on identity, context, and risk. With advancements in technology, OT systems that were traditionally isolated or manually operated are now increasingly interconnected, digitally monitored, and remotely controlled. This IT-OT convergence introduces new cybersecurity risks that make perimeter-based defenses and implicit trust models inadequate for safeguarding OT systems and the critical physical processes they control. This guidance supports OT owners and operators in addressing the unique challenges of transitioning to a ZT architecture, considering technology gaps from legacy infrastructure, operational constraints, and safety requirements. It focuses on establishing comprehensive asset visibility, proactively addressing supply chain risks, and implementing robust identity and access management while stressing the importance of layered security measures—including network segmentation, secure communication protocols, and vulnerability management. To learn more about ZT principles, visit Zero Trust CISA Product Survey We welcome your feedback. CISA Product Survey

CISA has added two new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2024-1708 ConnectWise ScreenConnect Path Traversal Vulnerability CVE-2026-32202 Microsoft Windows Protection Mechanism Failure Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information. Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of KEV Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the specified criteria.

View CSAF Summary Successful exploitation of this vulnerability could allow an attacker to disclose sensitive information. The following versions of NSA GRASSMARLIN are affected: GRASSMARLIN vers:all/* CVSS Vendor Equipment Vulnerabilities v3 5.5 NSA NSA GRASSMARLIN Improper Restriction of XML External Entity Reference Background Critical Infrastructure Sectors: Information Technology Countries/Areas Deployed: Worldwide Company Headquarters Location: United States Vulnerabilities Expand All + CVE-2026-6807 A vulnerability in GRASSMARLIN v3.2.1 allows crafted session data to trigger improper handling of XML input, which may result in unintended exposure of sensitive information. The flaw stems from insufficient hardening of the XML parsing process. View CVE Details Affected Products NSA GRASSMARLIN Vendor: NSA Product Version: NSA GRASSMARLIN: vers:all/* Product Status: known_affected Remediations Vendor fix NSA has indicated that the GRASSMARLIN project has reached end-of-life status as of 2017 and is no longer supported. The project is archived, and no patches or further updates are planned or expected. Relevant CWE: CWE-611 Improper Restriction of XML External Entity Reference Metrics CVSS Version Base Score Base Severity Vector String 3.1 5.5 MEDIUM CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Acknowledgments Grady DeRosa reported this vulnerability to CISA Legal Notice and Terms of Use This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy). Recommended Practices CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolating them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. CISA also recommends users take the following measures to protect themselves from social engineering attacks: Do not click web links or open attachments in unsolicited email messages. Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams. Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks. No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. Revision History Initial Release Date: 2026-04-28 Date Revision Summary 2026-04-28 1 Initial Publication Legal Notice and Terms of Use

CISA has added four new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2024-7399 Samsung MagicINFO 9 Server Path Traversal Vulnerability CVE-2024-57726 SimpleHelp Missing Authorization Vulnerability CVE-2024-57728 SimpleHelp Path Traversal Vulnerability CVE-2025-29635 D-Link DIR-823X Command Injection Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities established the KEV Catalog as a living list of known Common Vulnerabilities and Exposures (CVEs) that carry significant risk to the federal enterprise. BOD 22-01 requires Federal Civilian Executive Branch (FCEB) agencies to remediate identified vulnerabilities by the due date to protect FCEB networks against active threats. See the BOD 22-01 Fact Sheet for more information. Although BOD 22-01 only applies to FCEB agencies, CISA strongly urges all organizations to reduce their exposure to cyberattacks by prioritizing timely remediation of KEV Catalog vulnerabilities as part of their vulnerability management practice. CISA will continue to add vulnerabilities to the catalog that meet the specified criteria.

Defending against china-nexus covert networks of compromised devices executive summary Defending against China-nexus covert networks of compromised devices Explaining the widespread shift in tactics, techniques and procedures (TTPs) towards networks of compromised infrastructure, and how to defend against it Summary With support from the UK Cyber League, this advisory has been jointly released by the National Cyber Security Centre (NCSC-UK) and international partners: Australian Signals Directorate’s (ASD’s) Australian Cyber Security Centre (ACSC) Communications Security Establishment Canada’s (CSE’s) Canadian Centre for Cyber Security (Cyber Centre) Germany Federal Office for the Protection of the Constitution - Bundesamt für Verfassungsschutz (BfV) Germany Federal Intelligence Service – Bundesnachrichtendienst (BND) Germany Federal Office for Information Security - Bundesamt für Sicherheit in der Informationstechnik (BSI) Japan National Cybersecurity Office (NCO) - 国家サイバー統括室 Netherlands General Intelligence and Security Service - Algemene Inlichtingen- en Veiligheidsdienst (AIVD) Netherlands Defence Intelligence and Security Service - Militaire Inlichtingen- en Veiligheidsdienst (MIVD) New Zealand National Cyber Security Centre (NCSC-NZ) Spain National Cryptologic Centre – Centro Criptológico Nacional (CCN) Sweden National Cyber Security Centre - Nationellt cybersäkerhetscenter (NCSC-SE) United States Cybersecurity and Infrastructure Security Agency (CISA) United States Department of Defense Cyber Crime Center (DC3) United States Federal Bureau of Investigation (FBI) United States National Security Agency (NSA) Its purpose is to provide network defenders with the tools needed to defend against China-nexus cyber actors and their tactic of using large scale networks of compromised devices (covert networks) to route their cyber activity. Introduction Over the past few years there has been a major shift in the tactics, techniques and procedures (TTPs) used by China-nexus cyber actors, moving away from the use of individually procured infrastructure, and towards the use of externally provisioned, large-scale networks of compromised devices. The NCSC believes that the majority of China-nexus threat actors are using these networks (hereafter “covert networks”), that multiple covert networks have been created and are being constantly updated, and that a single covert network could be being used by multiple actors. These networks are mainly made up of compromised Small Office Home Office (SOHO) routers, as well as Internet of Things (IoT) and smart devices. Anyone who is a target of China-nexus cyber actors may be impacted by the use of covert networks. They have been used by Chinese state-sponsored actors Volt Typhoon to pre-position offensive cyber capabilities on critical national infrastructure. The group Flax Typhoon used a different covert network of compromised infrastructure to conduct cyber espionage. The use of covert networks of compromised devices - also known as botnets - to facilitate malicious cyber activity is not new, but China-nexus cyber actors are now using them strategically, and at scale. This advisory describes the typical makeup of a covert network and what they are being used for. It also includes protective advice for organizations being targeted by cyber activity using a covert network as an access vector. Covert Networks Covert networks are used to connect across the internet in a low-cost, low-risk, deniable way, disguising the origin and attribution of malicious activity. Actors have been observed using them for each phase of their Cyber Kill Chains, from performing scans as part of reconnaissance, to the delivery of malware, communicating with said malware, and exfiltrating stolen data from a victim. They can also be used for general deniable internet browsing, allowing threat actors to research exploitation techniques, new TTPs, and their victims without attribution. Some covert networks are also used by legitimate customers to browse the internet, making it challenging to attribute malicious activity. There is evidence that covert networks used by China-nexus actors are created and maintained by Chinese information security companies. A network known to network defenders as Raptor Train, which in 2024 infected more than 200,000 devices worldwide, was controlled and managed by the Chinese company, Integrity Technology Group. This company was also assessed by the FBI to be responsible for the computer intrusion activities attributed to China-based hackers known as Flax Typhoon. Botnet operations represent a significant threat to the UK by exploiting vulnerabilities in everyday internet-connected devices with the potential to carry out large-scale cyber attacks – NCSC Director of Operations, Paul Chichester Covert networks mostly consist of compromised SOHO routers, but they also pull in any vulnerable device they can exploit at scale. Raptor Train was made up of thousands of SOHO routers and IoT devices, such as web cameras and video recorders, as well as firewalls and Network Attached Storage (NAS) devices. The KV Botnet used by Volt Typhoon was mainly made up of vulnerable Cisco and NetGear routers. The edge devices were vulnerable because they were “end of life” – out of date and no longer receiving updates or security patches by their manufacturers. The cyber security industry has been aware of examples of these networks for some time and has publicly reported on the widespread scale of the threat and its implications. Mandiant Intelligence produced a public blog in May 2024 talking about covert networks in which they highlighted a key issue for defenders – indicator of compromise (IOC) Extinction. If a particular threat group could now come from one of many covert networks, each with potentially hundreds of thousands of endpoints, and each used by multiple threat actors, old network defense paradigms of static malicious IP block lists will be less effective. This is compounded by the dynamic nature of these networks where new nodes will be added as old devices are patched or removed from use. Typical Network Topology The number of covert networks used by China-nexus cyber actors is large, with new networks regularly developed and deployed. The existing covert networks change too, either because of defensive or legal action, or simply as a result of software updates and new exploits being used to target different technologies for incorporation into the network. Because of this, a description of all known covert networks in detail, including how they are constructed and how they communicate, would immediately be out of date – and for most network defenders would not be practically useful. However, most covert networks of compromised devices use the same basic set up. Understanding this generalized structure can aid researchers and defenders by helping them to understand which part of a network they may have found, and how to defend against it. A diagram illustrating the basic setup of a covert network. The diagram above illustrates the basic setup of a covert network, where typically an actor will connect to the network via an on-ramp or entry node. Their traffic will be forwarded through multiple compromised devices, used as traversal nodes, before exiting the network from an exit node, usually in the same geographic region as the target. Protective Advice Defending from attackers using covert networks is not straightforward, and defensive tactics will be different based on the levels of resource and the nature of the target organization. General advice for good cyber security practice should be followed, and some key messages can be found in the appendix of this advisory. The following advice is specifically tailored to steps which can be taken to combat the risk of attacks coming from large, dynamic networks of compromised devices. Further guidance for all organizations facing cyber security threats is available on the NCSC website. This guidance should be considered alongside all applicable laws and regulations of the UK and co-sealing countries relating to the security of networks and data. It will be each organization’s responsibility to ensure compliance with any such laws and regulations. Organizations should note that following the recommended actions set out below will not remove all risks. All organizations The NCSC recommends the following steps for all affected organizations to either take themselves, or ask their managed service and/or security providers to investigate for them: Map and understand network edge devices, developing a clear understanding of organizational assets and what should be connecting to them. Baseline normal connections, especially to corporate virtual private networks (VPNs) or other similar services. Would you expect connections from consumer broadband ranges? Leverage available dynamic threat feeds which include covert network infrastructure. Implement multifactor authentication for remote connections. Smaller organizations should consider creating and actioning a free NCSC Cyber Action Toolkit. Larger or more at-risk organizations Some more comprehensive measures may be appropriate if the risk to an organization is high enough, to be conducted either in-house or through a security provider: Apply IP address allow lists rather than deny lists for connections to corporate VPNs for remote workers. Use geographic allow lists or profile incoming connections based on operating system, time zones, and/or organization specific system configuration settings. Implement zero trust policies for connections. Enforce machine certificates for Secure Sockets Layer (SSL) connections. Reduce the internet-facing presence of the IT estate. Investigate machine learning techniques to profile normal network edge activity to detect and block anomalies. The NCSC's Cyber Essentials can help protect organizations of all sizes. Largest or most at-risk organizations If Advanced Persistent Threat (APT) tracking is part of an organization’s in-house capability, or if it is part of the service provided by a security vendor, consider tracking China-nexus covert networks as APTs in their own right. Active hunting – look for connections from IP addresses likely to be part of a covert network of compromised devices, for instance those hosting SOHO routers or IoT devices. Track and map covert networks reported by industry or government by looking at banners and certificates. Use threat reporting and threat feeds to create and implement dynamic blocklists and create alert rules to detect incoming threats. Consider using NetFlow feeds to look upstream and map covert networks to find new nodes. The NCSC Cyber Assessment Framework provides guidance for organizations under the highest levels of threat, including those operating essential services, in sectors such as energy, healthcare, transport, digital infrastructure and government. MITRE ATT&CK® This advisory has been compiled with respect to the MITRE ATT&CK® framework, a globally accessible knowledge base of adversary tactics and techniques based on real-world observations. Tactic ID Technique Procedure Resource Development T1584.005 Compromise Infrastructure: Botnet Botnets are used as core components of covert networks Resource Development T1584.008 Compromise Infrastructure: Network Devices Devices are compromised and added to botnets Resource Development T1583.003 Acquire Infrastructure: Virtual Private Server Virtual private servers (VPS) are used in covert networks, typically as on-ramps Command and Control T1090.003 Proxy: Multi-hop Proxy Used by China-nexus cyber actors to route traffic Appendix: Cyber Security Best Practices In addition to the protective advice outlined in this advisory, a number of cyber security best practices will also be useful in defending against the activity described in this advisory. Protect your devices and networks by keeping them up to date: use the latest supported versions, apply security updates promptly, use antivirus and scan regularly to guard against known malware threats. See NCSC Guidance: https://www.ncsc.gov.uk/collection/device-security-guidance/policies-and-settings/antivirus-and-other-security-software Prevent and detect lateral movement in your organization’s networks. See NCSC Guidance: https://www.ncsc.gov.uk/guidance/preventing-lateral-movement Implement architectural controls for network segregation. See NCSC Guidance: https://www.ncsc.gov.uk/guidance/10-steps-network-security Set up a security monitoring capability so you are collecting the data that will be needed to analyze network intrusions. See NCSC Guidance: https://www.ncsc.gov.uk/guidance/introduction-logging-security-purposes and https://www.ncsc.gov.uk/information/logging-made-easy Use modern systems and software. These have better security built-in. If you cannot move off out-of-date platforms and applications straight away, there are short term steps you can take to improve your position. See NCSC Guidance: https://www.ncsc.gov.uk/collection/mobile-device-guidance/managing-the-risks-from-obsolete-products Restrict intruders' ability to move freely around your systems and networks. Pay particular attention to potentially vulnerable entry points such as third-party systems with onward access to your core network. During an incident, disable remote access from third-party systems until you are sure they are clean. See NCSC Guidance: https://www.ncsc.gov.uk/guidance/preventing-lateral-movement and https://www.ncsc.gov.uk/guidance/assessing-supply-chain-security. Deploy a host-based intrusion detection system. A variety of products are available, free and paid-for, to suit different needs and budgets. Further information: Invest in preventing malware-based attacks across various scenarios. See NCSC Guidance: https://www.ncsc.gov.uk/guidance/mitigating-malware-and-ransomware-attacks Disclaimer This report draws on information derived from NCSC and industry sources. Any NCSC findings and recommendations made have not been provided with the intention of avoiding all risks and following the recommendations will not remove all such risk. Ownership of information risks remains with the relevant system owner at all times. Any reference to specific commercial entities, products, processes, or services by service mark, trademark, manufacturer, or otherwise, does not constitute or imply endorsement, recommendation, or favoring by co-sealers. UK readers should refer to the NCSC website for information about NCSC assured services. This information is exempt under the Freedom of Information Act 2000 (FOIA) and may be exempt under other UK information legislation. Refer any FOIA queries to ncscinfoleg@ncsc.gov.uk. All material is UK Crown Copyright ©