{ "document": { "category": "csaf_security_advisory", "csaf_version": "2.0", "distribution": { "tlp": { "label": "WHITE" } }, "lang": "en", "notes": [ { "category": "summary", "text": "An update is available that resolves a privately reported vulnerability to the product versions listed as affected in the advisory. An attacker who successfully exploited this vulnerability could cause the node running the product to stop or to become inaccessible.", "title": "Summary" }, { "category": "other", "text": "For additional instructions and support please contact your local ABB service organization. For contact information, see www.abb.com/contactcenters.\n\nInformation about ABB’s cyber security program and capabilities can be found at www.abb.com/cybersecurity.", "title": "Support" }, { "category": "legal_disclaimer", "text": "The information in this document is subject to change without notice, and should not be construed as a commitment by ABB.\n\nABB 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.\n\nThis 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.\n\nAll rights to registrations and trademarks reside with their respective owners.\n", "title": "Notice" }, { "category": "other", "text": "For any installation of software-related ABB products we strongly recommend the following (non-exhaustive) list of cyber security practices:\n\n– Allow only authorized users to access My Control System. Disable not used accounts and use secure passwords.\n\n– Use resource monitoring on your systems to detect resource exhaustion early.\n\n– Scan all data imported into your environment before use to detect potential malware infections.\n\n– Minimize network exposure for all applications and endpoints to ensure that they are not accessible from the Internet unless they are designed for such exposure and the intended use requires such.\n\n– Ensure all nodes are always up to date in terms of installed software, operating system, and firmware patches as well as anti-virus and firewall.\n\n– When remote access is required, use secure methods, such as Virtual Private Networks (VPNs). Recognize that VPNs may have vulnerabilities and should be updated to the most current version available. Also, understand that VPNs are only as secure as the connected devices.\n\nFor more information on recommended practices, please refer to the following documents listed in the reference section\n\n- 2PAA108749 My Control System – User Manual \n- 7PAA002031 My Control System (on-premise) System Hardening \n- 2PAA121208 My Control System (on-premise) – Installation and Configuration Manual", "title": "General security recommendations" }, { "category": "other", "text": "ABB has a rigorous internal cyber security continuous improvement process which involves regular testing with industry leading tools and periodic assessments to identify potential product issues. Occasionally an issue is determined to be a design or coding flaw with implications that may impact product cyber security.\n\nWhen a potential product vulnerability is identified or reported, ABB immediately initiates our vulnerability handling process. This entails validating if the issue is in fact a product issue, identifying root causes, determining what related products may be impacted, developing a remediation, and notifying end users and governmental organizations.\n\nThe resulting Cyber Security Advisory intends to notify customers of the vulnerability and provide details on which products are impacted, how to mitigate the vulnerability or explain workarounds that minimize the potential risk as much as possible. The release of a Cyber Security Advisory should not be misconstrued as an affirmation or indication of an active threat or ongoing campaign targeting the products mentioned here. If ABB is aware of any specific threats, it will be clearly mentioned in the communication.\n\nThe publication of this Cyber Security Advisory is an example of ABB’s commitment to the user community in support of this critical topic. Responsible disclosure is an important element in the chain of trust we work to maintain with our many customers. The release of an Advisory provides timely information which is essential to help ensure our customers are fully informed.", "title": "Purpose" }, { "category": "faq", "text": "What causes the vulnerability?\n- The vulnerability is caused by the lack of removing temporary generated files during data conversion in the ABB.Services.CT.CommonXML20.dll component of My Control System.\n\nWhat is “ABB.Services.CT.CommonXML20.dll”?\n- The above mentioned component of My Control System converts incoming data into a common defined shared model between MCS-DC and MCS platform. During this workflow it generates temporary data files used for the conversion process, which should be deleted after the conversion has been completed.\n\nWhat might an attacker use the vulnerability to do?\n- An attacker who successfully exploited this vulnerability could cause the affected system node to stop or to become inaccessible.\n\nHow could an attacker exploit the vulnerability?\n- 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. Recommended practices help mitigate such attacks, see section Mitigating Factors above.\n\nCould the vulnerability be exploited remotely?\n- 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.\n\nWhat does the update do?\n- The update removes the vulnerability by ensuring that newly generated temporary files will be deleted after conversion has been finished successfully.\n\nWhen this security advisory was issued, had this vulnerability been publicly disclosed?\n- No, ABB found this vulnerability through internal testing.\n\nWhen this security advisory was issued, had ABB received any reports that this vulnerability was being exploited?\n- No, ABB had not received any information indicating that this vulnerability had been exploited when this security advisory was originally issued.", "title": "Frequently Asked Questions" } ], "publisher": { "category": "vendor", "name": "ABB PSIRT", "namespace": "https://www.abb.com/global/en/company/about/cybersecurity/alerts-and-notifications" }, "references": [ { "category": "self", "summary": "ABB CYBERSECURITY ADVISORY - PDF Version ", "url": "https://search.abb.com/library/Download.aspx?DocumentID=7PAA025438&LanguageCode=en&DocumentPartId=&Action=Launch" }, { "category": "self", "summary": "ABB CYBERSECURITY ADVISORY - CSAF Version ", "url": "https://psirt.abb.com/csaf/2026/7paa025438.json" }, { "summary": "\nMy Control System – User Manual", "url": "https://search.abb.com/library/Download.aspx?DocumentID=2PAA108749&LanguageCode=en&DocumentPartId=&Action=Launch" }, { "summary": "\nMy Control System (on-premise) System Hardening", "url": "https://search.abb.com/library/Download.aspx?DocumentID=7PAA002031&LanguageCode=en&DocumentPartId=&Action=Launch" }, { "summary": "\nMy Control System (on-premise) – Installation and Configuration Manual", "url": "https://search.abb.com/library/Download.aspx?DocumentID=2PAA121208&LanguageCode=en&DocumentPartId=&Action=Launch" }, { "summary": "\nProduct Update ", "url": "https://search.abb.com/library/Download.aspx?DocumentID=2PAA121211&LanguageCode=en&DocumentPartId=&Action=Launch" } ], "title": "My Control System 26.5 – Disk space exhaustion due to incorrect temporary file cleanup after XML conversion", "tracking": { "current_release_date": "2026-10-15T00:30:00.000Z", "generator": { "date": "2026-10-14T08:54:12.757Z", "engine": { "name": "Secvisogram", "version": "2.6.14" } }, "id": "7PAA025438", "initial_release_date": "2026-10-15T00:30:00.000Z", "revision_history": [ { "date": "2026-10-15T00:30:00.000Z", "legacy_version": "A", "number": "1", "summary": "Initial version" } ], "status": "final", "version": "1" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version", "name": "26.4", "product": { "name": "ABB My Control System 26.4", "product_id": "AV1" } }, { "category": "product_version", "name": "26.5", "product": { "name": "ABB My Control System 26.5", "product_id": "AV2" } }, { "category": "product_version", "name": "26.6", "product": { "name": "ABB My Control System 26.6", "product_id": "FX1" } } ], "category": "product_name", "name": "My Control System" } ], "category": "vendor", "name": "ABB" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-17525", "cwe": { "id": "CWE-459", "name": "Incomplete Cleanup" }, "notes": [ { "category": "description", "text": "My Control System 26.5 – Disk space exhaustion due to incorrect temporary file cleanup after XML conversion.\n", "title": "CVE description" } ], "product_status": { "fixed": [ "FX1" ], "known_affected": [ "AV1", "AV2" ] }, "references": [ { "category": "external", "summary": "NVD - CVE-2026-17525", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-17525" } ], "remediations": [ { "category": "mitigation", "details": "Mitigating factors describe conditions and circumstances that make an attack that exploits the vulnerability difficult or less likely to succeed. Refer to section General security recommendations for further advice on how to keep your system secure.\n\nFor the reported issue there are no known mitigating factors.", "product_ids": [ "AV1", "AV2" ] }, { "category": "workaround", "details": "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 workarounds. Although these workarounds will not correct the underlying vulnerability, they can help block known attack vectors. When a workaround reduces functionality, this is identified below as “Impact of workaround”.\n\nAs a workaround for the reported issue the temporary files could be deleted manually:\n\n- Windows environments\n\nFor Windows environments, manually delete the contents of the directory below:\n\nC:\\Users\\\\AppData\\Local\\Temp\n\n- Edgenius environments\n\nNOTE - The procedure described below is a recovery measure only and does not prevent the issue itself. A permanent fix is available in My Control System version 26.6, but it is currently not possible to update existing installations of My Control System 26.5 due to limitations with Edgenius OS upgrades. These procedures are for temporary use only. A permanent solution and upgrade instructions will be provided once an Edgenius OS upgrade path is available.\n\nFor Edgenius installations, manually run the following command within the host environment.\n\nkubectl delete pod -l app.kubernetes.io/component=mcs-masterkpi -n my-control-system\n\nThis restarts the container that can build up temporary files over time and ensures these files are cleaned up. The workaround should only be performed while there is no analysis in progress.", "product_ids": [ "AV1", "AV2" ] }, { "category": "vendor_fix", "details": "The problem is corrected in the following product versions:\n\n- My Control System 26.6 (all deployment types)\n\nABB recommends that customers apply the update at earliest convenience.\n\nNOTE - Installations of MCS on Edgenius with version 26.5 or earlier are not eligible for an update to MCS 26.6, as this requires an OS upgrade to EdgeniusOS 3.3.0 or later. Support for the required OS upgrade is expected with the upcoming EdgeniusOS 4.0.0 and the corresponding MCS package. Until an upgrade path is available, please follow the workaround in this document. A follow up communication will be provided once the OS upgrade path is available. \n\nMore information can be found in Product Update with document ID: 2PAA121211 listed in the reference section.\n\nIn addition to performing an update on eligible systems, it is recommended to manually delete the contents of the following system folder one time after the installation of My Control System 26.6 has been completed. This applies to Windows-based installations only.\n\nWindows temp directory: C:\\Users\\\\AppData\\Local\\Temp For Edgenius installations, please follow instructions provided below to clean up temporary files used by the MCS containers.", "product_ids": [ "AV1", "AV2" ] } ], "scores": [ { "cvss_v3": { "attackComplexity": "LOW", "attackVector": "ADJACENT_NETWORK", "availabilityImpact": "HIGH", "baseScore": 5.2, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "environmentalScore": 4.9, "environmentalSeverity": "MEDIUM", "exploitCodeMaturity": "FUNCTIONAL", "integrityImpact": "NONE", "privilegesRequired": "LOW", "remediationLevel": "TEMPORARY_FIX", "reportConfidence": "CONFIRMED", "scope": "UNCHANGED", "temporalScore": 4.9, "temporalSeverity": "MEDIUM", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:H/E:F/RL:T/RC:C", "version": "3.1" }, "products": [ "AV1", "AV2" ] } ], "title": "CVE-2026-17525" } ] }