In the Linux kernel, the following vulnerability has been resolved: net: openvswitch: conntrack: avoid modifying shared unconfirmed ct entry In a case where skb with an unconfirmed ct entry gets cloned, we may end up committing both but with different sets of extensions. The series of events: 1. The first clone wants to commit and runs the helpers wiring up the extension pointer into the expectation list. 2. Then it looses the confirmation keeping the entry unconfirmed. 3. Second clone now wants to commit labels and adds the new extension for that breaking the pointer in the expectation list causing UAF on the destruction path later. While this is possible to trigger, there should be no practical network pipeline where committing both clones without modifications into the same zone is needed. So, let's just reset the entry in case for some reason we got an skb with a shared one during commit. This doesn't affect any known use cases, but avoids any potential problems with sharing and modification of the unconfirmed ct entry. The fixes tag points to the introduction of helpers, since that's the main UAF trigger for the sharing.
Fix
Microsoft's update · Important
- Release Notes — azl3 kernel 6.6.157.1-1 on Azure Linux 3.0 · build 6.6.159.1-1
From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-31.
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 5
- StatusReceived → PublishedNVD modified 2026-10-24 14:09
- StatusPublished → ReceivedNVD modified 2026-10-24 14:16
- CVSS7.8 (v3.1, CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)NVD modified 2026-10-24 14:16
- StatusReceived → PublishedNVD modified 2026-10-19 09:20
- First seenunscoredNVD modified 2026-10-19 10:19
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 8
- https://git.kernel.org/stable/c/26b2bd70d22457556e2fa01cbf1192cb1a94d619
- https://git.kernel.org/stable/c/37e3c878b183a115f9a114067f9ef3b408ad27fb
- https://git.kernel.org/stable/c/457e0df1b5711fbeb7ba1b6bfd826f5ef30e7e55
- https://git.kernel.org/stable/c/55e5256adf3940e71802e2f749cacf81518726b0
- https://git.kernel.org/stable/c/707c2dc77891a874f4e8c52c285a511079164ec8
- https://git.kernel.org/stable/c/de41ee24f77b0fc45397db3e277cae2adbd43dfe
- https://git.kernel.org/stable/c/e0fa5ea434b7e8467ef3adc64e3858b1ca2a642d
- https://git.kernel.org/stable/c/e2829ae5459ddb5fce526b2e84697edf6c0c3cef