ESB-2026.4625

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.4625 K000161061: crypto: algif_aead - Revert to operating out-of-place (Copy Fail) CVE-2026-31431 5 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: F5 Products Publisher: F5 Networks Operating System: F5 Resolution: Patch/Upgrade CVE Names: CVE-2026-31431 Original Bulletin: https://my.f5.com/manage/s/article/K000161061 Comment: CVSS (Max): 7.8 CVE-2026-31431 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) CVSS Source: kernel.org Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H The following are listed in the CISA Known Exploited Vulnerabilities (KEV) Catalog: CISA KEV CVE(s): CVE-2026-31431 CISA KEV URL: https://www.cisa.gov/known-exploited-vulnerabilities-catalog EPSS (Max): 4.0% (88th) CVE-2026-31431 2026-05-04 - --------------------------BEGIN INCLUDED TEXT-------------------- K000161061: crypto: algif_aead - Revert to operating out-of-place (Copy Fail) CVE-2026-31431 Published Date: May 1, 2026 Security Advisory Description In the Linux kernel, the following vulnerability has been resolved: crypto: algif_aead - Revert to operating out-of-place This mostly reverts commit 72548b093ee3 except for the copying of the associated data. There is no benefit in operating in-place in algif_aead since the source and destination come from different mappings. Get rid of all the complexity added for in-place operation and just copy the AD directly. (CVE-2026-31431) Impact For products with None in the Versions known to be vulnerable column, there is no impact. For products with ** in the various columns, F5 is still researching the issue and will update this article after confirming the required information. F5 Support has no additional information about this issue. Security Advisory Status To determine if your product and version have been evaluated for this vulnerability, refer to the Evaluated products box. To determine if your release is known to be vulnerable, the components or features that are affected by the vulnerability, and for information about releases, point releases, or hotfixes that address the vulnerability, refer to the following tables. You can also use iHealth to diagnose a vulnerability for BIG-IP, BIG-IQ, and F5OS systems. For more information about using iHealth, refer to K27404821: Using F5 iHealth to diagnose vulnerabilities. For more information about security advisory versioning, refer to K51812227: Understanding security advisory versioning. In this section o BIG-IP Next o BIG-IP and BIG-IQ o F5 Distributed Cloud and NGINX Services o F5OS o NGINX o Other products BIG-IP Next Note: After a fix is introduced for a given minor branch, that fix applies to all subsequent maintenance and point releases for that branch, and no additional fixes for that branch will be listed in the table. For example, when F5 releases a fix in BIG-IP Next SPK 2.0.1, the fix also applies to 2.0.2 and all later 2.0.x releases. For more information, refer to K51812227: Understanding security advisory versioning. +-------------+------+-----------------+----------+----------+----------------+ | | |Versions known to|Fixes |Severity/ |Vulnerable | |Product |Branch|be vulnerable^1 |introduced|CVSS score|component or | | | | |in |^2 |feature | +-------------+------+-----------------+----------+----------+----------------+ |BIG-IP Next |2.x |** |** | | | |SPK +------+-----------------+----------+** |** | | |1.x |** |** | | | +-------------+------+-----------------+----------+----------+----------------+ |BIG-IP Next |2.x |** |** | | | |CNF +------+-----------------+----------+** |** | | |1.x |** |** | | | +-------------+------+-----------------+----------+----------+----------------+ |BIG-IP Next | | | | | | |for |2.x |** |** |** |** | |Kubernetes | | | | | | +-------------+------+-----------------+----------+----------+----------------+ ^1F5 evaluates only software versions that have not yet reached the End of Technical Support (EoTS) phase of their lifecycle. For more information, refer to the Security hotfixes section of K4602: Overview of the F5 security vulnerability response policy. ^2Starting with the August 2024 Quarterly Security Notification, F5 will provide the CVSS v4.0 base score in addition to the CVSS v3.1 score, for first-party security issues only. The CVSS score link takes you to a resource outside of MyF5, and the content may be removed without our knowledge. For more information about how F5 uses CVSS v4.0, refer to K000140363: Overview of CVSS v4.0 in F5 security advisories. **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. BIG-IP and BIG-IQ Note: After a fix is introduced for a given minor branch, that fix applies to all subsequent maintenance and point releases for that branch, and no additional fixes for that branch will be listed in the table. For example, when a fix is introduced in 16.1.2.1, the fix also applies to 16.1.2.2, and all later 16.1.x releases (16.1.3.x, 16.1.4.x). For more information, refer to K51812227: Understanding security advisory versioning. +--------------+------+----------------+----------+-----------+---------------+ | | |Versions known |Fixes |Severity/ |Vulnerable | |Product |Branch|to be vulnerable|introduced|CVSS score^|component or | | | |^1 |in |2 |feature | +--------------+------+----------------+----------+-----------+---------------+ | |21.x |** |** | | | |BIG-IP (all +------+----------------+----------+ | | |modules) |17.x |** |** |** |** | | +------+----------------+----------+ | | | |16.x |** |** | | | +--------------+------+----------------+----------+-----------+---------------+ |BIG-IQ | | | | | | |Centralized |8.x |** |** |** |** | |Management | | | | | | +--------------+------+----------------+----------+-----------+---------------+ ^1F5 evaluates only software versions that have not yet reached the End of Technical Support (EoTS) phase of their lifecycle. For more information, refer to the Security hotfixes section of K4602: Overview of the F5 security vulnerability response policy. ^2Starting with the August 2024 Quarterly Security Notification, F5 will provide the CVSS v4.0 base score in addition to the CVSS v3.1 score, for first-party security issues only. The CVSS score link takes you to a resource outside of MyF5, and the content may be removed without our knowledge. For more information about how F5 uses CVSS v4.0, refer to K000140363: Overview of CVSS v4.0 in F5 security advisories. **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. F5 Distributed Cloud and NGINX Services +--------------------+-------------------+-------------------------------+ |Service |Severity/CVSS score|Vulnerable component or feature| +--------------------+-------------------+-------------------------------+ |F5 Distributed Cloud|** |** | +--------------------+-------------------+-------------------------------+ |F5 Silverline |** |** | +--------------------+-------------------+-------------------------------+ |NGINX One Console |** |** | +--------------------+-------------------+-------------------------------+ **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the services indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. F5OS +-------+------+-------------------+-----------+------------+-----------------+ | | |Versions known to |Fixes |Severity/ |Vulnerable | |Product|Branch|be vulnerable^1 |introduced |CVSS score^2|component or | | | | |in | |feature | +-------+------+-------------------+-----------+------------+-----------------+ |F5OS-A |1.x |** |** |** |** | +-------+------+-------------------+-----------+------------+-----------------+ |F5OS-C |1.x |** |** |** |** | +-------+------+-------------------+-----------+------------+-----------------+ ^1F5 evaluates only software versions that have not yet reached the End of Technical Support (EoTS) phase of their lifecycle. For more information, refer to the Security hotfixes section of K4602: Overview of the F5 security vulnerability response policy. ^2Starting with the August 2024 Quarterly Security Notification, F5 will provide the CVSS v4.0 base score in addition to the CVSS v3.1 score, for first-party security issues only. The CVSS score link takes you to a resource outside of MyF5, and the content may be removed without our knowledge. For more information about how F5 uses CVSS v4.0, refer to K000140363: Overview of CVSS v4.0 in F5 security advisories. **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. NGINX +------------+------+-----------------+----------+-----------+----------------+ | | |Versions known to|Fixes |Severity/ |Vulnerable | |Product |Branch|be vulnerable^1 |introduced|CVSS score^|component or | | | | |in |2 |feature | +------------+------+-----------------+----------+-----------+----------------+ |NGINX Plus |R3x |** |** |** |** | +------------+------+-----------------+----------+-----------+----------------+ |NGINX Open |1.x |** |** |** |** | |Source | | | | | | +------------+------+-----------------+----------+-----------+----------------+ | |3.x |** |** | | | |NGINX Agent +------+-----------------+----------+** |** | | |2.x |** |** | | | +------------+------+-----------------+----------+-----------+----------------+ |NGINX | | | | | | |Instance |2.x |** |** |** |** | |Manager | | | | | | +------------+------+-----------------+----------+-----------+----------------+ |F5 WAF for |5.x |** |** |** |** | |NGINX | | | | | | +------------+------+-----------------+----------+-----------+----------------+ |NGINX App |5.x |** |** | | | |Protect WAF +------+-----------------+----------+** |** | | |4.x |** |** | | | +------------+------+-----------------+----------+-----------+----------------+ |F5 DoS for |4.x |** |** |** |** | |NGINX | | | | | | +------------+------+-----------------+----------+-----------+----------------+ |NGINX App |4.x |** |** |** |** | |Protect DoS | | | | | | +------------+------+-----------------+----------+-----------+----------------+ |NGINX |2.x |** |** | | | |Gateway +------+-----------------+----------+** |** | |Fabric |1.x |** |** | | | +------------+------+-----------------+----------+-----------+----------------+ | |5.x |** |** | | | |NGINX +------+-----------------+----------+ | | |Ingress |4.x |** |** |** |** | |Controller +------+-----------------+----------+ | | | |3.x |** |** | | | +------------+------+-----------------+----------+-----------+----------------+ ^1F5 evaluates only software versions that have not yet reached the End of Technical Support (EoTS) phase of their lifecycle. For more information, refer to the Security hotfixes section of K4602: Overview of the F5 security vulnerability response policy. ^2Starting with the August 2024 Quarterly Security Notification, F5 will provide the CVSS v4.0 base score in addition to the CVSS v3.1 score, for first-party security issues only. The CVSS score link takes you to a resource outside of MyF5, and the content may be removed without our knowledge. For more information about how F5 uses CVSS v4.0, refer to K000140363: Overview of CVSS v4.0 in F5 security advisories. **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. Other products +-------+------+-------------------+-----------+------------+-----------------+ | | |Versions known to |Fixes |Severity/ |Vulnerable | |Product|Branch|be vulnerable^1 |introduced |CVSS score^2|component or | | | | |in | |feature | +-------+------+-------------------+-----------+------------+-----------------+ |Traffix|5.x |** |** |** |** | |SDC | | | | | | +-------+------+-------------------+-----------+------------+-----------------+ |F5 AI |1.x |** |** |** |** | |Gateway| | | | | | +-------+------+-------------------+-----------+------------+-----------------+ ^1F5 evaluates only software versions that have not yet reached the End of Technical Support (EoTS) phase of their lifecycle. For more information, refer to the Security hotfixes section of K4602: Overview of the F5 security vulnerability response policy. ^2Starting with the August 2024 Quarterly Security Notification, F5 will provide the CVSS v4.0 base score in addition to the CVSS v3.1 score, for first-party security issues only. The CVSS score link takes you to a resource outside of MyF5, and the content may be removed without our knowledge. For more information about how F5 uses CVSS v4.0, refer to K000140363: Overview of CVSS v4.0 in F5 security advisories. **Confirmation of vulnerability or non-vulnerability is not presently available. F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. Security Advisory Recommended Actions F5 is still researching the issue for the products indicated and will update this article with the most current information as soon as it has been confirmed. F5 Support has no additional information on this issue. Related Content o K41942608: Overview of MyF5 security advisory articles o K12201527: Overview of Quarterly Security Notifications o K51812227: Understanding security advisory versioning o K4602: Overview of the F5 security vulnerability response policy o K4918: Overview of the F5 critical issue hotfix policy o K39757430: F5 product and services lifecycle policy index o K9970: Subscribe to email notifications regarding F5 products and security announcements o K9957: Creating a custom RSS feed to view new and updated documents - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. 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