CVE-2026-8461: Heap out-of-bounds write via odd slice_height in FFmpeg MagicYUV decoder

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-18 · updated 2026-07-23
Weakness: CWE-787

Description

An out-of-bounds write vulnerability in FFmpeg's libavcodec library, specifically in the MagicYUV decoder, allows denial-of-service and, in some cases, can be exploited for remote code execution. This vulnerability is associated with the file libavcodec/magicyuv.C. This issue affects FFmpeg before version 8.1.2.

Affected products

FFmpeg: before 8.1.2 — fixed in 8.1.2

How to fix

Upgrade to a fixed version: FFmpeg 8.1.2. Check the vendor advisory for mitigations.

References

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23159
https://access.redhat.com/errata/RHSA-2026:43711
https://access.redhat.com/security/cve/CVE-2026-8461
https://bugzilla.redhat.com/show_bug.cgi?id=2490308
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-8461.json

Get alerted when CVE-2026-8461 or the next vulnerability affects your stack