An out-of-bounds write vulnerability was found in GStreamer's H.266/VVC PPS picture partition parser in gst-plugins-bad. In the multi-slice-in-tile processing of gst_h266_parser_parse_picture_partition() (gsth266parser.c), the loop iterates without checking that the slice index stays within bounds, writing past three fixed-size arrays (slice_height_in_ctus, slice_top_left_ctu_x, slice_top_left_ctu_y) in the GstH266PPS structure. While the initial proof-of-concept demonstrated a 4-byte out-of-bounds write, the code permits larger writes across multiple iterations. A crafted H.266/VVC media file can trigger this vulnerability.
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.