CVE-2025-11680

Name	CVE-2025-11680
Description	Out-of-bounds Write in unfilter_scanline in warmcat libwebsockets allows, when the LWS_WITH_UPNG flag is enabled during compilation and the HTML display stack is used, to write past a heap allocated buffer possibly causing a crash, when the user visits an attacker controlled website that contains a crafted PNG file with a big width value that causes an integer overflow which value is used for determining the size of a heap allocation.
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
libwebsockets (PTS)	bullseye	4.0.20-2	fixed
	bullseye (security)	4.0.20-2+deb11u1	fixed
	bookworm	4.1.6-3	fixed
	trixie	4.3.5-1+deb13u1	fixed
	forky, sid	4.3.5-3	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libwebsockets	source	(unstable)	(not affected)

Notes

- libwebsockets <not-affected> (Vulnerable code introduced in 4.4.0)
Introduced in: https://libwebsockets.org/git/libwebsockets/commit?id=48907fca0a25c39ce35692c527cb8aa82ee60d85 (v4.4.0)
Fixed in: https://libwebsockets.org/git/libwebsockets/commit?id=2b715249f39291c86443b969a1088d59b6a89b78