CVE-2026-73213

Coturn: `addr_less_eq()` does a component-wise IPv6 comparison instead of a lexicographic one, letting an authenticated TURN client bypass `denied-peer-ip`/`allowed-peer-ip` IPv6 ranges (TURN-specific SSRF)

Published: Aug 11, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-863

N/ACVSS

NVD MITRE

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.

No summary for this CVE yet.

Weaknesses

CWE-863

Affected Products

coturn

oss-project

coturnOn-prem

Networking Infrastructure / load-balancer-proxy

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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References

https://github.com/coturn/coturn/commit/6c13608c28a04af5d63abddd7565a0dcc4771c28

github.com

https://github.com/coturn/coturn/releases/tag/4.16.0

github.com

https://github.com/coturn/coturn/security/advisories/GHSA-4v97-rxjj-4f99

github.com

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