FFmpeg versions 2.7 through 8.1.2 contain an out-of-bounds write vulnerability in the TDSC video decoder that allows remote attackers to cause heap corruption by supplying a crafted AVI file that changes frame dimensions across TDSF frames. The tdsc_parse_tdsf() function fails to unreference the existing reference frame before calling av_frame_get_buffer(), causing tdsc_blit() and tdsc_yuv2rgb() to write attacker-controlled pixel data beyond the end of the undersized reference frame buffer, resulting in a process crash and potential code execution.