CVE-2026-125209
HIGH
NVD
CVSS Score
7.8
Severity
HIGH
Published
Nov 09, 2026
Vendor
unknown
Description
FFmpeg before 8.1.3 and 9.x before 9.0.2 contains a heap buffer overflow vulnerability in the DVD subtitle encoder that underestimates RLE output size for odd-width rectangles. Attackers can supply files with crafted bitmap subtitles that, when transcoded to the dvdsub encoder, write past the output buffer and corrupt heap memory.
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24486
- https://github.com/FFmpeg/FFmpeg
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/dvdsubenc.c#L344
- https://github.com/FFmpeg/FFmpeg/commit/8702f12c9daa199cc4d7c17164b13c3cdcdc2436
- https://www.vulncheck.com/advisories/ffmpeg-before-8.1.3-and-9-x-before-9.0.2-heap-buffer-overflow-via-dvdsubenc-c