CVE-2026-98491

net: openvswitch: conntrack: avoid modifying shared unconfirmed ct entry

State
Published
Severity
7.8 High
Published
Oct 18, 2026
Updated
Oct 24, 2026
Reserved
Sep 25, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
3.17.8 HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux

Weaknesses

The record names no weakness.

Affected Products

ProductVersions
LinuxLinux
  • cae3a2627520c3795b54533c5328b77af3405dbe to before e0fa5ea434b7e8467ef3adc64e3858b1ca2a642dAffected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before 37e3c878b183a115f9a114067f9ef3b408ad27fbAffected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before 707c2dc77891a874f4e8c52c285a511079164ec8Affected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before de41ee24f77b0fc45397db3e277cae2adbd43dfeAffected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before 55e5256adf3940e71802e2f749cacf81518726b0Affected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before e2829ae5459ddb5fce526b2e84697edf6c0c3cefAffected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before 457e0df1b5711fbeb7ba1b6bfd826f5ef30e7e55Affected
  • cae3a2627520c3795b54533c5328b77af3405dbe to before 26b2bd70d22457556e2fa01cbf1192cb1a94d619Affected
LinuxLinux
  • 4.3Affected
  • before 4.3Not affected
  • 5.10.271 through 5.10.*Not affected
  • 5.15.222 through 5.15.*Not affected
  • 6.1.189 through 6.1.*Not affected
  • 6.6.158 through 6.6.*Not affected
  • 6.12.112 through 6.12.*Not affected
  • 6.18.55 through 6.18.*Not affected
  • 7.2.9 through 7.2.*Not affected
  • 7.3 and laterNot affected

References

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