CVE-2026-125266FFmpeg FFmpeg
NVD
Vulnerability Summary
FFmpeg through 9.0.2 contains an uninitialized stack memory disclosure vulnerability in old_codec23() of libavcodec/sanm.c that leaks stack bytes into decoded frames. Attackers can supply a crafted LucasArts SMUSH/SANM animation using codec 23 with an inline table to expose decoder process stack memory in output video.
CVSS v4.0 Base Metrics — Score 4.8 (MEDIUM)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:NAttack VectorLocal
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)Low
Integrity (Vulnerable System)None
Availability (Vulnerable System)None
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 3.3)
CVSS v3.1 Base Metrics — Score 3.3 (LOW)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:NAttack VectorLocal
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone
Affected & Patched Versions
- FFmpeg FFmpeg >= 8.0 and <= 9.0.2
- FFmpeg FFmpeg 9.0.2
What to do
Fix it during your normal patch cycle. No exploitation is confirmed yet.
- Check whether you run FFmpeg FFmpeg and which version.
- Update to a patched version listed above, then confirm the new version.
Timeline
- Nov 9, 2026Published
- Nov 13, 2026Record last modified
Score, severity and exploitation changes are tracked from the day Watchtower started logging them.
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Set up CVE alertsExternal References
- Referencehttps://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25718
- Patchhttps://github.com/FFmpeg/FFmpeg/commit/d42cb1925987cc27899441ce39fa7bd2647dc72e
- Referencehttps://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/sanm.c#L799
- Referencehttps://github.com/FFmpeg/FFmpeg
- Referencehttps://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-stack-memory-disclosure-via-sanm-codec-23
Data last checked: Nov 13, 2026 18:08 UTC