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.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/2c2f6e96e31795ae95a8f8323a493ffbc493111f Patch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24590 Issue Tracking, Patch
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 4.8 · ffmpegNVD modified 2026-10-14 23:55
Affected (CPE criteria) 1
cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*
References 5
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/2c2f6e96e31795ae95a8f8323a493ffbc493111f Patch
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24590 Issue Tracking, Patch
- https://ffmpeg.org/ Product
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavutil/hdr_dynamic_metadata.c#L374-L385 Product
- https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-memory-disclosure-via-hdr10-metadata-serializer Third Party Advisory