# CVE-2026-73214: coturn: Coturn is a free open source implementation of TURN and STUN Server

CVE-2026-73214 is fixed in coturn on 1 platform by DEBIAN-CVE-2026-73214 (version 4.18.0-1), released August 11, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-73214
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0058
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 11, 2026

## 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | coturn Debian 14 | 4.18.0-1 | [DEBIAN-CVE-2026-73214](https://patchblox.com/security/data/fix/linux/debian-cve-2026-73214.md) | Aug 11, 2026 |

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Data as of 2026-11-09T13:31:49Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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