FFmpeg through 9.0.2 contains an out-of-bounds memory access vulnerability in the encode_frame() function of libavcodec/huffyuvenc.c, because encode_init() never validates minimum frame dimensions for the median predictor. Attackers can supply a tiny video, such as a 2-pixel-wide or 1-2-pixel-tall frame, that causes negative sub_median_pred lengths and out-of-bounds reads and writes when transcoded to huffyuv or ffvhuff, crashing the encoder.