High 7.4Published Jul 10, 2026

CVE-2026-53450Coturn: IPv4-mapped 127.0.0.1 bypasses default loopback peer protection

Updated under an hour ago (Oct 27, 2026, 12:23 PM ET)

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Every CVE for coturn

Exploited in the last 30 days

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, coturn rejects loopback peers by default unless allow-loopback-peers is enabled, but the default loopback guard can be bypassed by using the IPv4-mapped IPv6 peer address ::ffff:127.0.0.1 in a TURN XOR-PEER-ADDRESS attribute. ioa_addr_is_loopback checks for the literal IPv6 loopback shape before IPv4-mapped IPv6 handling, so good_peer_addr does not apply the default loopback rejection and an authenticated TURN client can expose services bound only to localhost on the coturn host through TURN relay traffic. This issue is fixed in version 4.13.0.

CVSS: 7.4 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L
Weakness (CWE): CWE-918
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Jul 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

coturn coturn coturn:coturn (from the name)	before 4.13.0	CNA record
coturn_project coturn coturn_project:coturn	before 4.13.0	NVD

References

References

https://github.com/coturn/coturn/security/advisories/GHSA-w4hf-cr3w-6h79	x-refsource-confirm, third-party-advisory
https://github.com/coturn/coturn/commit/b057acbebe721c8f2f202ddad5e16289e295c754	x-refsource-misc, patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.