CVE-2026-80636

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: conntrack: revert ct extension genid infrastructure

This infrastructure is not used anymore after moving ct timeout and

helper to use datapath refcount to track object use.

Revert commit c56716c69ce1 ("netfilter: extensions: introduce extension

genid count") this patch disables all ct extensions (leading to NULL)

for unconfirmed conntracks, when this is only targeted at ct helper and

ct timeout. There is also codebase that dereferences the ct extension

without checking for NULL which could lead to crash.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References