FFmpeg: Integer overflow in ff_prores_kostya_encode_init (CVE-2026-125259)
FFmpeg through 9.0.2 contains an integer overflow vulnerability in ff_prores_kostya_encode_init() due to 32-bit arithmetic miscalculating frame_size_upper_bound for large frame dimensions.
CVE search metadata
CVE search record: CVE-2026-125259. Severity: high. CVSS: 7.8. KEV: no. Product: FFmpeg (<= 9.0.2). Brief: FFmpeg: Integer overflow in ff_prores_kostya_encode_init (CVE-2026-125259). Brief link: https://feed.craftedsignal.io/briefs/2026-11-ffmpeg-integer-overflow-d0e0d71a/
Triage facts
Revision 1- Applicability
- FFmpeg (<= 9.0.2)
- Evidence
- Unknown
- Severity
- High
- Sources
- 1 public source
- Freshness
- Revision 1Nov 9, 23:59 UTC
- Vulnerabilities
- 1 CVE
- Source quality
- A2Roughly even chance
FFmpeg through 9.0.2 contains an integer overflow vulnerability in the ff_prores_kostya_encode_init() function caused by 32-bit arithmetic miscalculating frame_size_upper_bound for large frame dimensions. Attackers can supply a high-resolution video transcoded with the prores_ks encoder, which causes encode_frame() to write slices past an undersized packet buffer, leading to heap memory corruption.