CVE-2026-125208 FFmpeg through 9.0.2 V4L2 M2M Encoder Out-of-Bounds Write in v4l2_buffers.c

High 7.3 Published 9 Nov 2026 Updated 10 Nov 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-125208?

CVE-2026-125208 is a high-severity vulnerability in FFmpeg, published on 9 Nov 2026.

Official description

FFmpeg through 9.0.2 contains an out-of-bounds write vulnerability in v4l2_buffer_swframe_to_buf() in libavcodec/v4l2_buffers.c because cumulative plane offsets are not checked against the V4L2 buffer length. Attackers can supply crafted video whose dimensions or padding cause unsigned wraparound in v4l2_bufref_to_buf(), making memcpy() write past the mmaped driver buffer during V4L2 M2M encoding.

Weakness: CWE-787

Which versions are affected by CVE-2026-125208?

How do I fix CVE-2026-125208?

No fix has been published for CVE-2026-125208 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-125208 being exploited?

There is no known exploitation of CVE-2026-125208 in the wild and no public exploit code.

Sources

Also known as GHSA-4rxc-7q96-c86h, UBUNTU-CVE-2026-125208.