CVE-2026-80636

Name	CVE-2026-80636
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bookworm	6.1.176-1	vulnerable
	bookworm (security)	6.1.187-1	vulnerable
	trixie (security), trixie	6.12.107-1	fixed
	forky	7.1.13-1	fixed
	sid	7.2.6-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version
linux	source	bullseye	(not affected)
linux	source	trixie	6.12.100-1
linux	source	(unstable)	7.1.5-1

[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/35e21a4dccc5c255ba59ccfbfeb4629ed21da972 (7.2-rc1)