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.
History

Tue, 11 Aug 2026 18:00:00 +0000

Type Values Removed Values Added
Description 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.
Title coturn allocates a full per-peer SSL/session before verifying the DTLS cookie, enabling source-spoofing/botnet state-exhaustion DoS
Weaknesses CWE-400
CWE-770
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-08-11T17:34:51.860Z

Reserved: 2026-08-11T14:41:20.121Z

Link: CVE-2026-73214

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-11T18:18:26.773

Modified: 2026-08-11T18:18:26.773

Link: CVE-2026-73214

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.