CVE-2026-68552 Coturn: uint16_t truncation overflow in STUN message length causes TCP stream framing bypass

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, an unauthenticated remote client can send a STUN message over TCP or TLS with a body-length field from 65520 through 65532, causing the uint16t len variable in stungetmessagelenstr in src/client/nsturnmsg.c to...

CVE-2026-68552

Coturn versions before 4.15.0 have a uint16_t overflow in stun_get_message_len_str() in src/client/ns_turn_msg.c: a crafted STUN body-length (65520–65532) causes the variable to wrap when STUN_HEADER_LENGTH is added, desynchronizing the TCP/TLS stream parser and dropping only the attacker's conne...