CVE-2026-125255 FFmpeg through 9.0.2 Use-After-Free in MJPEG Hardware-Accelerated Decoding

Medium 5.8 Published 9 Nov 2026 Updated 10 Nov 2026

Exploited in the wild: Not known
Fix: None listed

What is CVE-2026-125255?

CVE-2026-125255 is a medium-severity vulnerability in FFmpeg, published on 9 Nov 2026.

Official description

FFmpeg through 9.0.2 contains a use after free vulnerability in libavcodec/mjpegdec.c that allows attackers to trigger freed buffer reads by sending a SOF marker without a preceding SOI. Attackers can supply crafted MJPEG streams causing ff_mjpeg_decode_sof() to pass a stale raw_image_buffer pointer to hwaccel decoders like NVDEC, crashing applications or leaking heap contents.

Weakness: CWE-416

Which versions are affected by CVE-2026-125255?

How do I fix CVE-2026-125255?

No fix has been published for CVE-2026-125255 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-125255 being exploited?

There is no known exploitation of CVE-2026-125255 in the wild and no public exploit code.

Sources

Also known as GHSA-phr3-qwpx-974c, UBUNTU-CVE-2026-125255.