Description
FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in av_dynamic_hdr_plus_to_t35() that leaves up to three payload bytes uninitialized when tone_mapping_flag is 0. Attackers can supply crafted Matroska T.35 BlockAdditional or HEVC/AV1 SEI metadata so that remuxing or transcoding writes leaked process memory into output files.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| FFmpeg | FFmpeg | ≤ 9.0.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | ffmpeg | No fix yet | — |
| Debian 13 | ffmpeg | No fix yet | — |
| Debian 12 | ffmpeg | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | ffmpeg | No fix yet | — |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 24.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 22.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 20.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 18.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 16.04 LTS | ffmpeg | No fix yet | — |
| Ubuntu Pro 14.04 LTS | libav | No fix yet | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | ffmpeg-7 +4 | No fix yet | — |
Advisories 1
- WID-SEC-2026-3820 ffmpeg: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 8, 2026
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24590 patch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/2c2f6e96e31795ae95a8f8323a493ffbc493111f patch
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavutil/hdr_dynamic_metadata.c#L374-L385 technical-description
- https://ffmpeg.org/ product
- VulnCheck Advisory: FFmpeg through 9.0.2 Uninitialized Memory Disclosure via HDR10+ Metadata Serializer third-party-advisory