CVE-2026-125212: FFmpeg · Heap-based Buffer Overflow
Affects FFmpegSource CVE Database V5
Not known to be exploited · CVSS 7.3 High.
Data as of 9 Nov 2026, 20:20 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 7.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 7.0 |
CVSS:4.0/AV:L/AC:H/AT:P/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
Users should monitor FFmpeg vendor advisories for updates addressing this vulnerability. Until a fix is released, avoid processing untrusted input streams that may change resolution mid-stream with VideoToolbox encoders or implement input validation to prevent oversized frames.
Description
CVE-2026-125212 is a heap-based buffer overflow vulnerability in FFmpeg versions up to 9.0.2. It occurs in the VideoToolbox encoder component when frames larger than the encoder's configured dimensions are copied into undersized buffers. This can happen if an attacker supplies input whose resolution increases mid-stream without proper rescaling, potentially causing application crashes or memory corruption.
References
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25682 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/commit/9b99973b2bbecee0b7e1e57035b95498b42f54a6 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/videotoolboxenc.c (opens in a new tab)
- github.com/FFmpeg/FFmpeg (opens in a new tab)
- vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-buffer-overflow-via-videotoolbox-encoder (opens in a new tab)