CVE-2026-125187FFmpeg FFmpeg
NVD
Vulnerability Summary
FFmpeg through 9.0.2 contains a reachable assertion vulnerability in the TTA encoder's tta_encode_frame() in libavcodec/ttaenc.c, which never reserves output packet space for the 4-byte CRC. Attackers can supply audio whose sample values and length produce a small, poorly compressible final frame, triggering the av_assert0() in flush_put_bits() and aborting applications transcoding to TTA.
CVSS v4.0 Base Metrics — Score 6.8 (MEDIUM)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NAttack VectorLocal
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionPassive
Confidentiality (Vulnerable System)None
Integrity (Vulnerable System)None
Availability (Vulnerable System)High
Confidentiality (Subsequent System)None
Integrity (Subsequent System)None
Availability (Subsequent System)None
Show CVSS v3.x metrics (score 5.5)
CVSS v3.1 Base Metrics — Score 5.5 (MEDIUM)
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HAttack VectorLocal
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
Affected & Patched Versions
- FFmpeg FFmpeg <= 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 9, 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/25694
- Patchhttps://github.com/FFmpeg/FFmpeg/commit/29a629e788c4343ff2e923095b8f38769fe2e470
- Referencehttps://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/ttaenc.c#L93
- Referencehttps://github.com/FFmpeg/FFmpeg
- Referencehttps://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-tta-encoder-reachable-assertion-via-tta-encode-frame
Data last checked: Nov 13, 2026 21:28 UTC