CVE-2026-125177 json
FFmpeg through 9.0.2 Uninitialized Heap Memory Disclosure via MSCC/SRGC Decoder
published 2d ago modified yesterday also EUVD-2026-120266
- cvss
- 3.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 2%
- public exploits
- 0
- none known
Summary
FFmpeg through 9.0.2 contains an information disclosure vulnerability in the MSCC/SRGC decoder in libavcodec/mscc.c that outputs uninitialized heap bytes when RLE data ends early. Attackers can craft an MSCC or SRGC stream, such as in AVI, whose RLE data terminates early so the decoded frame exposes leftover heap memory to viewers of the output.
Patch / fix
Is CVE-2026-125177 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerExploit prediction
0.13% chance of exploitation in the next 30 days, higher than 2% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 4.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
| CNA | 4.0 | 4.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| NVD | 3.1 | 3.3 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
Affected products
- FFmpeg FFmpeg
Classification
- Weakness
-
- CWE-908 Use of Uninitialized Resource
References
-
github.com
/FFmpeg/FFmpeg/commit/263a85e2a2127396f8a2b0c329ec798e1ea015ad
patch
-
code.ffmpeg.org
/FFmpeg/FFmpeg/pulls/24465
issue-tracking
-
github.com
/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/mscc.c#L236
technical-description
-
github.com
/FFmpeg/FFmpeg
product
-
vulncheck.com
/advisories/ffmpeg-through-9.0.2-uninitialized-heap-memory-disclosure-via-mscc-srgc-decoder
third-party-advisory
Sources
- CVE List CVE-2026-125177
- NVD CVE-2026-125177
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.