CVE-2026-65704

Name	CVE-2026-65704
Description	FFmpeg through 8.1.2 contains an out-of-bounds write vulnerability that allows attackers to cause heap corruption by supplying a crafted ffconcat file processed with the -safe 0 flag. The TY demuxer's demux_audio() function decrements packet size without bounds checking, producing a negative size value that is passed to memcpy() in shorten_decode_frame(), where conversion to size_t wraps the value to near SIZE_MAX and triggers reads beyond the source allocation and writes far beyond the Shorten decoder's bitstream buffer.
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
ffmpeg (PTS)	bullseye	7:4.3.7-0+deb11u1	vulnerable
	bullseye (security)	7:4.3.9-0+deb11u2	vulnerable
	bookworm, bookworm (security)	7:5.1.9-0+deb12u1	vulnerable
	trixie (security), trixie	7:7.1.5-0+deb13u1	vulnerable
	forky, sid	7:8.1.2-2	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
ffmpeg	source	(unstable)	(unfixed)

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23767
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/de771bd52774a52d45b0e2c82e56995a1ef40df7