CVE-2026-73213 Server-side request forgery in coturn
An authenticated TURN client can bypass IPv6 access controls to relay traffic to restricted peers, effectively bypassing SSRF protections in Coturn.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-73213?
CVE-2026-73213 is a medium-severity server-side request forgery vulnerability in coturn, published on 11 Aug 2026. Any signed-in user can exploit it over the network, 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, addr_less_eq() in src/client/ns_turn_ioaddr.c uses a component-wise comparison for native IPv6 min-max intervals in ioa_addr_in_range(), allowing an authenticated TURN client to relay to an IPv6 peer that is numerically within a configured non-prefix-aligned denied-peer-ip range but is classified as outside it. This issue is fixed in version 4.16.0.
Weakness: CWE-863
Which versions are affected by CVE-2026-73213?
How do I fix CVE-2026-73213?
Upgrade to a fixed version.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-73213 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73213 exists.
Sources
Also known as DEBIAN-CVE-2026-73213, GHSA-4v97-rxjj-4f99, MINI-w4jg-hjf3-3wg5, UBUNTU-CVE-2026-73213.