FFmpeg versions 3.0 through 8.1.2 contain an out-of-bounds write vulnerability in the vf_swaprect video filter that allows attackers to corrupt heap memory by supplying a crafted NV12 video frame with odd width dimensions. The filter_frame() function reuses a temporary row buffer sized for plane 0's single-byte pixel step across all planes, causing an 18-byte memcpy into a 17-byte heap allocation when processing the two-byte-per-sample interleaved chroma plane of a 17x16 NV12 frame, resulting in heap corruption and process crash with potential for code execution.
https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23779
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/a7e38b617b32f996beaa371bbf04b39907d7a527
Published: 2026-07-23
Updated: 2026-07-24
Base Score: 7.2
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Severity: High
Base Score: 8.5
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
Severity: High
EPSS: 0.00133