CVE-2026-98491

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

HIGH
7.8
CVSS Score
Published: October 18, 2026 at 03:16 PM UTC
Updated: October 24, 2026 at 02:16 PM UTC
1 product affected across 1 vendorLinux Kernel

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Severity
HIGH7.8
Exploit prediction
EPSS 0.2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.3cae3a2627520c3795b54533c5328b77af3405dbe
Vendor states this is fixed in 5.10.271 (unaffected)
Vendor states this is fixed in 5.15.222 (unaffected)
Vendor states this is fixed in 6.1.189 (unaffected)
Vendor states this is fixed in 6.12.112 (unaffected)
Vendor states this is fixed in 6.18.55 (unaffected)
Vendor states this is fixed in 6.6.158 (unaffected)
Vendor states this is fixed in 7.2.9 (unaffected)
Vendor states this is fixed in 7.3 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

CVSS

7.8HIGHLinux
Vector?

Quick Info

StatusRECEIVED

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