CVE-2026-53450 | Coturn is a free open source implementation of TURN and STUN… | CVSS 7.4 HIGH

Description

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.

Metadata

CVE ID: CVE-2026-53450
State: PUBLISHED
Assigner: GitHub_M
Reserved: 2026-06-09 16:31 UTC
Published: 2026-07-10 18:05 UTC
Last updated: 2026-07-10 19:03 UTC
Primary CWE: CWE-918
CWE-918: Server-Side Request Forgery (SSRF)
Vendor / Product: coturn / coturn
Sources: cve.org · NVD

Severity & Metrics

7.4 HIGH CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L

SSVC — CISA Coordinator

Exploitation: PoC
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
coturn	coturn	—	< 4.13.0

Weakness (CWE)

CWE	Source	Description
CWE-918	cna	CWE-918: Server-Side Request Forgery (SSRF)

CVSS scores (1)

Score	Severity	Version	Source	Vector
7.4	HIGH	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L

References (2)

https://github.com/coturn/coturn/security/advisories/GHSA-w4hf-cr3w-6h79 https://github.com/coturn/coturn/security/advisories/GHSA-w4hf-cr3w-6h79
https://github.com/coturn/coturn/commit/b057acbebe721c8f2f202ddad5e16289e295c754 https://github.com/coturn/coturn/commit/b057acbebe721c8f2f202ddad5e16289e295c754