CVSS 4.0
6.8 mediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-125066 ffmpeg ffmpeg: Unchecked Return Value
Medium (6.8) in ffmpeg ffmpeg. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
On this page
FFmpeg through 9.0.2 contains a NULL pointer dereference vulnerability in the Cirrus Logic AccuPak (CLJR) decoder in libavcodec/cljrdec.c because decode_frame() ignores init_get_bits() failure. Attackers can supply a crafted AVI file with a 2^28-byte CLJR frame that overflows the bit count, causing reads from a NULL buffer and crashing the process.
Severity
CVSS 3.1
5.5 mediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 8th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-09. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-252 Unchecked Return Value
- OWASP Top 10
- A10:2025 Mishandling of Exceptional Conditions
- Published
- Modified
- Assigned by
- VulnCheck (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| FFmpeg | through 9.0.2 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 26.10, Pro:16.04:LTS, Pro:18.04:LTS and 4 more | ffmpeg | no fix listed | UBUNTU-CVE-2026-125066 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu.
References
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25704
- https://github.com/FFmpeg/FFmpeg
- https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/cljrdec.c#L54
- https://github.com/FFmpeg/FFmpeg/commit/d40c1b12811814fc6c2d0816527b003d8510ea06
- https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-null-pointer-dereference-in-cljr-video-decoder