Description
FFmpeg before 9.0 has a signed integer overflow in libavformat/mov.c. In mov_read_ispe(), uint32_t width/height values from a crafted HEIF ispe box are stored into signed int fields without bounds checking, allowing values exceeding INT_MAX to become negative. In read_image_grid(), accumulating these values causes signed integer overflow (undefined behavior per C17 section 6.5), which on x86 wraps to a small positive value, bypassing downstream validity checks.
Affected products
ffmpeg: ffmpeg
References2
- code.ffmpeg.org/FFmpeg/FFmpeg/commit/059eb2e853c1f62b8df1b73be9… Patch
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23455 Issue TrackingPatch
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 1 · as of 9 November 2026
- CWE
- CWE-190
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