CVE-2026-125211 FFmpeg through 9.0.2 Heap Corruption via libaribcaption ASS Error Cleanup
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-125211?
CVE-2026-125211 is a high-severity vulnerability in FFmpeg, published on 9 Nov 2026.
Official description
FFmpeg through 9.0.2 contains an out-of-bounds read and invalid free vulnerability in aribcaption_trans_ass_subtitle() in libavcodec/libaribcaption.c that frees subtitle rectangles using region_count instead of num_rects. Attackers can supply crafted ARIB captions whose later region exceeds the 8 KiB AVBPrint limit, triggering cleanup that frees out-of-bounds pointers and corrupts the heap.
Weakness: CWE-125
Which versions are affected by CVE-2026-125211?
How do I fix CVE-2026-125211?
No fix has been published for CVE-2026-125211 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-125211 being exploited?
There is no known exploitation of CVE-2026-125211 in the wild and no public exploit code.
Sources
Also known as GHSA-x5qr-4g8r-vgwj, UBUNTU-CVE-2026-125211.