A vulnerability in GStreamer's gst-plugins-good H.264 RTP depayloader element allows remote attackers to trigger an out-of-bounds heap read by sending a malformed RTP packet. This flaw arises from a signed/unsigned integer conversion error when processing MTAP16 or MTAP24 multi-time aggregation RTP packets, causing a length counter underflow. Exploitation can crash the GStreamer pipeline (denial of service) and potentially expose adjacent heap memory in relay or transcoding scenarios.