CVE-2026-25068

Name	CVE-2026-25068
Description	alsa-lib versions 1.2.2 up to and including 1.2.15.2, prior to commit 5f7fe33, contain a heap-based buffer overflow in the topology mixer control decoder. The tplg_decode_control_mixer1() function reads the num_channels field from untrusted .tplg data and uses it as a loop bound without validating it against the fixed-size channel array (SND_TPLG_MAX_CHAN). A crafted topology file with an excessive num_channels value can cause out-of-bounds heap writes, leading to a 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)
References	DLA-4469-1
Debian Bugs	1126629

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
alsa-lib (PTS)	bullseye	1.2.4-1.1	vulnerable
	bullseye (security)	1.2.4-1.1+deb11u1	fixed
	bookworm	1.2.8-1	vulnerable
	trixie	1.2.14-1	vulnerable
	forky, sid	1.2.15.3-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
alsa-lib	source	bullseye	1.2.4-1.1+deb11u1		DLA-4469-1
alsa-lib	source	(unstable)	(unfixed)			1126629

Notes

[trixie] - alsa-lib <no-dsa> (Minor issue)
[bookworm] - alsa-lib <no-dsa> (Minor issue)
Introduced by: https://github.com/alsa-project/alsa-lib/commit/b6c9afb4f59bb678dc834028680d579f47dc273b (v1.2.2)
Fixed by: https://github.com/alsa-project/alsa-lib/commit/5f7fe33002d2d98d84f72e381ec2cccc0d5d3d40