A flaw was found in GStreamer's H.266 codec parser library (libgstcodecparsers). An out-of-bounds write vulnerability exists in the DCI parsing function, where a reserved field value is incorrectly accepted, causing the parser to write beyond the bounds of an internal structure. An attacker could exploit this by providing a specially crafted H.266 bitstream to a third-party application that uses this library API, potentially causing a crash or memory corruption. No standard GStreamer pipeline element currently invokes the affected code path.