| Name | CVE-2019-9721 |
| Description | A denial of service in the subtitle decoder in FFmpeg 3.2 and 4.1 allows attackers to hog the CPU via a crafted video file in Matroska format, because handle_open_brace in libavcodec/htmlsubtitles.c has a complex format argument to sscanf. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 926666 |
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 | fixed |
| bullseye (security) | 7:4.3.8-0+deb11u3 | fixed |
| bookworm, bookworm (security) | 7:5.1.6-0+deb12u1 | fixed |
| sid, trixie | 7:7.1.1-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| ffmpeg | source | stretch | (not affected) | | | |
| ffmpeg | source | (unstable) | 7:4.1.3-1 | | | 926666 |
| libav | source | jessie | (not affected) | | | |
| libav | source | (unstable) | (unfixed) | | | |
Notes
[stretch] - ffmpeg <not-affected> (Vulnerable code not present)
https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/894995c41e0795c7a44f81adc4838dedc3932e65
[jessie] - libav <not-affected> (Vulnerable code not present)