CVE-2026-75147

FFmpeg before commit 983dae9 contains an out-of-bounds read in the AV1 RTP packetizer (libavformat/rtpenc_av1.c). The keyframe detection loop that searches for a sequence header OBU advanced its pointer and remaining-size counter by the encoded header length plus the OBU payload size without first bounding the OBU size against the remaining data. A crafted OBU size causes the remaining-size counter to wrap to a positive value, causing the next loop iteration to dereference a pointer beyond the end of the packet buffer. A crafted AV1 input packet muxed to RTP triggers the out-of-bounds read.

Score

CVSS 3.1 7.1 High

Status

Awaiting Analysis - disclosure@vulncheck.com

Published

2026-08-19

Last modified

2026-10-27

Weaknesses

CWE-125

Affected products

• Ffmpeg (Ffmpeg)

References

• https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/983dae9c19f46c87d597598c0fd2f2fcee0ad2f8
• https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24096
• https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-read-in-av1-rtp-packetizer-via-rtpenc-av1-c