Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.