CVE-2026-125220 json
FFmpeg through 9.0.2 Mimic Decoder Deadlock via Frame Threading Failure
published 2d ago modified yesterday also EUVD-2026-120309
- cvss
- 5.5
- 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 a deadlock vulnerability in mimic_decode_frame() in libavcodec/mimic.c that fails to report frame progress when init_get_bits8() fails. Attackers can supply a crafted file with an oversized Mimic intra frame followed by inter frames to hang frame-threaded decoding indefinitely.
Patch / fix
Is CVE-2026-125220 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 FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2d ago
Exploit 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 | 6.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.5 | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 6.8 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/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 |
Affected products
- FFmpeg FFmpeg
Classification
- Weakness
-
- CWE-833 Deadlock
References
-
github.com
/FFmpeg/FFmpeg/commit/db77b0b8318ddb38b5a3227724da088a325a4308
patch
-
code.ffmpeg.org
/FFmpeg/FFmpeg/pulls/25718
issue-tracking
-
github.com
/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/mimic.c#L403
technical-description
-
github.com
/FFmpeg/FFmpeg
product
-
vulncheck.com
/advisories/ffmpeg-through-9.0.2-mimic-decoder-deadlock-via-frame-threading-failure
third-party-advisory
Sources
- CVE List CVE-2026-125220
- NVD CVE-2026-125220
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