CVE-2026-125099: FFmpeg · Use of Uninitialized Resource
Affects FFmpegSource CVE Database V5
Not known to be exploited · CVSS 4.8 Medium.
Data as of 9 Nov 2026, 20:35 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 4.8 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 3.3 |
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/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 GEM .img images to mitigate risk.
Description
CVE-2026-125099 is a medium severity vulnerability in FFmpeg up to version 9.0.2. It involves an uninitialized memory disclosure in the GEM raster image decoder component, where crafted GEM .img images can cause uninitialized heap memory to be copied into decoded frames, potentially exposing sensitive data.
References
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25715 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/commit/e578999fa3c5f7efac1ea70bb7c2a7682013c7c9 (opens in a new tab)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/gemdec.c (opens in a new tab)
- github.com/FFmpeg/FFmpeg (opens in a new tab)
- vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-memory-disclosure-via-gem-raster-decoder (opens in a new tab)