CVE-2026-73214 Denial of service in coturn
Unauthenticated remote attackers can exhaust server memory via crafted DTLS packets, causing denial of service in coturn.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-73214?
CVE-2026-73214 is a high-severity denial of service vulnerability in coturn, published on 11 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Which versions are affected by CVE-2026-73214?
How do I fix CVE-2026-73214?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-73214 being exploited?
There is no known exploitation of CVE-2026-73214 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-73214, GHSA-5x2p-4vqj-f6m4, MINI-q3gc-xjhq-mp56, UBUNTU-CVE-2026-73214.