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.

CVSS 4.0

6.9CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

7.1CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H

EPSS

0.1% chance of exploitation in the next 30 days; higher than 1% of CVEs (scores of 2026-10-25)

CWE

CWE-125

Published

2026-08-19

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

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

Check your stackJSON