CVE-2026-56109

Name	CVE-2026-56109
Description	The Advanced Linux Sound Architecture (ALSA) library before 1.2.16.1 contains a double-free vulnerability in parse_def() in src/conf.c that allows attackers to corrupt memory by supplying maliciously crafted ALSA configuration text. When parsing nested compound or array configuration blocks, parse_def() fails to check return values before continuing, causing snd_config_delete() to be called twice on the same already-freed node, resulting in a NULL-pointer write or invalid memory read.
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
alsa-lib (PTS)	bullseye	1.2.4-1.1	vulnerable
	bullseye (security)	1.2.4-1.1+deb11u1	vulnerable
	bookworm	1.2.8-1	vulnerable
	trixie	1.2.14-1	vulnerable
	forky, sid	1.2.16-1	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	(unstable)	(unfixed)	unimportant

Notes

https://lore.kernel.org/alsa-devel/CAGt8pqBU0p2voB+qHxWGcNJrKHAcBhAyHUUBPLBN-Yj_SiV6MQ@mail.gmail.com/
Fixed by: https://github.com/alsa-project/alsa-lib/commit/536dd6f8affdf5197c12a63a71c92a70b2833cc0 (v1.2.16.1)
Doesn't cross any meaningful security boundary