CVE-2026-125187

EUVD-2026-120276
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
VulnCheckCNA
5.5 MEDIUM
LOCAL
LOW
NONE
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources (CNA/ADP records, vendor advisories, Enginsight analysis).
VendorProductVersionSource
ffmpegffmpeg
𝑥
≤ 9.0.2
CNA
Common Weakness Enumeration
References
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25694
https://github.com/FFmpeg/FFmpeg
https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/ttaenc.c#L93
https://github.com/FFmpeg/FFmpeg/commit/29a629e788c4343ff2e923095b8f38769fe2e470
https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-tta-encoder-reachable-assertion-via-tta-encode-frame