CVE-2026-73214
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.16.0, dtls_server_input_handler() and create_new_connected_udp_socket() in src/apps/relay/dtls_listener.c retain OpenSSL dtls1_reassemble_fragment() state for a 35-byte fragmented ClientHello declaring a 650,000-byte handshake before cookie validation, allowing an unauthenticated remote sender using fresh UDP tuples to exhaust memory without TURN credentials, a completed handshake, a valid cookie, or source spoofing. This issue is fixed in version 4.16.0.
Weakness
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.16.0, dtls_server_input_handler() and create_new_connected_udp_socket() in src/apps/relay/dtls_listener.c retain OpenSSL dtls1_reassemble_fragment() state for a 35-byte fragmented ClientHello declaring a 650,000-byte handshake before cookie validation, allowing an unauthenticated remote sender using fresh UDP tuples to exhaust memory without TURN credentials, a completed handshake, a valid cookie, or source spoofing. This issue is fixed in version 4.16.0.
References
- https://github.com/coturn/coturn/commit/37e13d1d60af8f1422c01b5e9f1c6bc355d03b85
- https://github.com/coturn/coturn/commit/beb4de9dcb6a475129595b943c9a34264420df09
- https://github.com/coturn/coturn/pull/2003
- https://github.com/coturn/coturn/pull/2012
- https://github.com/coturn/coturn/releases/tag/4.16.0
- https://github.com/coturn/coturn/security/advisories/GHSA-5x2p-4vqj-f6m4
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