Description
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.1, good_peer_addr() in src/server/ns_turn_server.c uses ioa_addr_in_range() in src/client/ns_turn_ioaddr.c without canonicalizing IPv4-compatible, 6to4, and 64:ff9b::/96 NAT64 address forms, allowing an authenticated RFC 6062 TCP CONNECT relay client to bypass an IPv4 denied-peer-ip range when the Coturn host has a useful translation route. This issue is fixed in version 4.13.1.
References6
- github.com/coturn/coturn/commit/cf4b4952de48510d38415b96300da5f…
- github.com/coturn/coturn/commit/d49ee56aa9fe748af064853d5e430ee…
- github.com/coturn/coturn/pull/1945
- github.com/coturn/coturn/pull/1947
- github.com/coturn/coturn/releases/tag/4.13.1
- github.com/coturn/coturn/security/advisories/GHSA-2x4g-wx24-48m4
Metrics
- CVSS 4.0
-
5.8
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 43 · as of 12 November 2026
- CWE
- CWE-284CWE-918
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