CVE-2026-66041

Description

FFmpeg 7.0 through 8.1.2, fixed in commit 4da9812, contains a heap out-of-bounds write vulnerability in the vf_quirc filter that allows an attacker to corrupt heap memory by supplying a crafted PGS/SUP subtitle file with mismatched frame dimensions. Attackers can provide a subtitle file whose second presentation has larger dimensions than its first, causing av_image_copy_plane() to copy data exceeding the initial allocation size into the undersized libquirc grayscale image buffer, resulting in heap corruption and process crash with potential for code execution.

References

• https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/4da9812e25894fb51d62a8875cfa8eb39b5e20f5
• https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23625
• https://www.vulncheck.com/advisories/ffmpeg-heap-out-of-bounds-write-via-vf-quirc-filter