CVE-2025-40240

Name	CVE-2025-40240
Description	In the Linux kernel, the following vulnerability has been resolved: sctp: avoid NULL dereference when chunk data buffer is missing chunk->skb pointer is dereferenced in the if-block where it's supposed to be NULL only. chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list instead and do it just before replacing chunk->skb. We're sure that otherwise chunk->skb is non-NULL because of outer if() condition.
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)	5.10.244-1	vulnerable
	bookworm	6.1.148-1	vulnerable
	bookworm (security)	6.1.158-1	fixed
	trixie	6.12.57-1	fixed
	trixie (security)	6.12.48-1	vulnerable
	forky	6.17.9-1	fixed
	sid	6.17.10-1	fixed

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

Package	Type	Release	Fixed Version
linux	source	bookworm	6.1.158-1
linux	source	trixie	6.12.57-1
linux	source	(unstable)	6.17.6-1

https://git.kernel.org/linus/441f0647f7673e0e64d4910ef61a5fb8f16bfb82 (6.18-rc3)