CVE-2026-74663

Name	CVE-2026-74663
Description	In the Linux kernel, the following vulnerability has been resolved: net/sched: reject overly deep qdisc hierarchies Deep qdisc hierarchies can lead to excessive recursion in qdisc tree walkers and exhaust the kernel stack. The existing loop check does not cover the create-and-graft path, so a hierarchy can still be extended by creating a new child qdisc below an already deep parent. Store the hierarchy depth in struct Qdisc and update it when qdiscs are grafted. Reject new child qdiscs once the parent is already at the maximum allowed depth.
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)	bullseye	5.10.223-1	vulnerable
	bullseye (security)	5.10.262-1	vulnerable
	bookworm	6.1.176-1	vulnerable
	bookworm (security)	6.1.180-1	vulnerable
	trixie	6.12.94-1	vulnerable
	trixie (security)	6.12.101-1	vulnerable
	forky	7.1.8-2	vulnerable
	sid	7.1.9-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
linux	source	(unstable)	7.1.9-1

https://git.kernel.org/linus/dedd34b0f2310e28c5f6d4875cfbf4b7ed821c01 (7.2-rc7)