CVE-2026-125187 FFmpeg through 9.0.2 TTA Encoder Reachable Assertion via tta_encode_frame()

Medium 6.8 Published 9 Nov 2026 Updated 9 Nov 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-125187?

CVE-2026-125187 is a medium-severity vulnerability in FFmpeg, published on 9 Nov 2026.

Official description

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.

Weakness: CWE-617

Which versions are affected by CVE-2026-125187?

How do I fix CVE-2026-125187?

No fix has been published for CVE-2026-125187 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-125187 being exploited?

There is no known exploitation of CVE-2026-125187 in the wild and no public exploit code.

Sources

Also known as GHSA-88jf-7jvx-8545, UBUNTU-CVE-2026-125187.