Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

GStreamer-SA-2026-0030 affects gst-plugins-base RTCP SDES parsing in versions before 1.28.4. Static review of upstream 1.28.3 confirmed that gst_rtcp_packet_sdes_get_entry() in gst-libs/gst/rtp/gstrtcpbuffer.c checks the entry type and length header but does not verify that the attacker-controlled entry value length fits within the received RTCP packet. A crafted SDES entry delivered to an active RTP/RTCP session can therefore cause an out-of-bounds read, with a possible receiver crash or limited adjacent-memory disclosure. The parser also undercounts the packet length by four bytes in several SDES walk functions; this undercount alone appears to make those loop bounds stricter, while the missing entry-value check is independently sufficient for the read. The flaw was verified by static source review only; no build or PoC was run. Upstream fixed this in gst-plugins-base 1.28.4 (GStreamer merge request 11791).