CVE-2026-125229: FFmpeg · Out-of-bounds Write
Affects FFmpegSource CVE Database V5
Not known to be exploited · CVSS 8.5 High.
Data as of 9 Nov 2026, 20:17 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 8.5 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 7.8 |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 9 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 9 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| FFmpegFFmpeg | Affected
| Fixed in– |
GitHubFFmpegpkg:github/FFmpegOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Until a fix is available, avoid processing untrusted or suspiciously small video frames with FFmpeg versions up to 9.0.2.
Description
CVE-2026-125229 is a high-severity out-of-bounds memory access vulnerability in FFmpeg versions up to 9.0.2. It occurs in the encode_frame() function of libavcodec/huffyuvenc.c due to insufficient validation of minimum frame dimensions in encode_init(). This allows crafted tiny video frames to cause negative length calculations, leading to out-of-bounds reads and writes that crash the encoder.
References
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25573 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/commit/45f98d0819efe2b7ce93e9034b7e6a4ed6700621 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/huffyuvenc.c (opens in a new tab)
- github.com/FFmpeg/FFmpeg (opens in a new tab)
- vulncheck.com/advisories/ffmpeg-through-9.0.2-out-of-bounds-memory-access-in-huffyuv-ffvhuff-median-predictor (opens in a new tab)