Medium severity · published Aug 11, 2026
CVE-2026-73212
coturn peer-IP ACL canonicalization & scope bypass on the RFC 6062 TCP CONNECT relay path → internal-network SSRF and proven internal root RCE
5.8
CVSS
0.5%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 42% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
coturn · coturn
< 4.13.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-73212
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-73212
github.com
https://github.com/coturn/coturn/commit/cf4b4952de48510d38415b96300da5fc674bfdda
github.com
https://github.com/coturn/coturn/commit/d49ee56aa9fe748af064853d5e430eec1ccc3cbc
github.com
https://github.com/coturn/coturn/pull/1945
github.com
https://github.com/coturn/coturn/pull/1947
github.com
https://github.com/coturn/coturn/releases/tag/4.13.1
github.com
https://github.com/coturn/coturn/security/advisories/GHSA-2x4g-wx24-48m4
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