Linux Kernel up to 6.19.13 pfkey_sockaddr_size uninitialized pointer

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.19.13. The impacted element is the function pfkey_sockaddr_size. Executing a manipulation can lead to uninitialized pointer. The identification of this vulnerability is CVE-2026-43088. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in Linux Kernel up to 6.19.13. This vulnerability affects the function pfkey_sockaddr_size. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. The CWE definition for the vulnerability is CWE-824. The product accesses or uses a pointer that has not been initialized. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: af_key: zero aligned sockaddr tail in PF_KEY exports PF_KEY export paths use `pfkey_sockaddr_size()` when reserving sockaddr payload space, so IPv6 addresses occupy 32 bytes on the wire. However, `pfkey_sockaddr_fill()` initializes only the first 28 bytes of `struct sockaddr_in6`, leaving the final 4 aligned bytes uninitialized. Not every PF_KEY message is affected. The state and policy dump builders already zero the whole message buffer before filling the sockaddr payloads. Keep the fix to the export paths that still append aligned sockaddr payloads with plain `skb_put()`: - `SADB_ACQUIRE` - `SADB_X_NAT_T_NEW_MAPPING` - `SADB_X_MIGRATE` Fix those paths by clearing only the aligned sockaddr tail after `pfkey_sockaddr_fill()`.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-43088 since 05/01/2026. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/21/2026).

The vulnerability scanner Nessus provides a plugin with the ID 317729 (SUSE SLES12 Security Update : kernel (SUSE-SU-2026:2068-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.19.14 eliminates this vulnerability. Applying the patch 2e74f974359b5382ecbe8536abbb5b837eb6c724/426c355742f02cf743b347d9d7dbdc1bfbfa31ef is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (317729) and CERT Bund (WID-SEC-2026-1385). Once again VulDB remains the best source for vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Microsoft Azure Linux

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.19.0
• 6.19.1
• 6.19.2
• 6.19.3
• 6.19.4
• 6.19.5
• 6.19.6
• 6.19.7
• 6.19.8
• 6.19.9
• 6.19.10
• 6.19.11
• 6.19.12
• 6.19.13

License

• open-source

Website

• Vendor: https://www.kernel.org/

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Once again VulDB remains the best source for vulnerability data.

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