FFmpeg through 9.0.2 Heap Buffer Overflow via LCEVC Enhancement Decoding

Advisories

FFmpeg through 9.0.2 Heap Buffer Overflow via LCEVC Enhancement Decoding

Severity: high
Date: 11/9/2026
Affecting: FFmpeg >= 7.1, <= 9.0.2
CVE: CVE-2026-125262
CWE: CWE-787 Out-of-bounds Write
CVSS: 8.5
CVSS V4 Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
References: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25067
Patch Commit
https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/lcevcdec.c#L224
https://github.com/FFmpeg/FFmpeg
Credit: Ayoub Nabil Boubagrat, Joshua Rogers (AISLE Research), Michael Niedermayer
Description: FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in libavcodec/lcevcdec.c because LCEVC output picture dimensions are not validated against the allocated frame. Attackers can embed crafted LCEVC enhancement data with differing global configurations in H.264 or HEVC streams to corrupt heap memory in decoding applications.

Ready to get Started?

Explore VulnCheck, a next-generation Cyber Threat Intelligence platform, which provides exploit and vulnerability intelligence to help you prioritize and remediate vulnerabilities that matter.

Vulnerability Prioritization
Prioritize vulnerabilities that matter based on the threat landscape and defer vulnerabilities that don't.
Early Warning System
Real-time alerting of changes in the vulnerability landscape so that you can take action before the attacks start.

Schedule a Demo