CVE-2026-53450

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{"bugzilla": {"description": "coturn: Coturn: Localhost services exposed via IPv4-mapped IPv6 address bypass", "id": "2499130", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2499130"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.4", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L", "status": "draft"}, "cwe": "CWE-289", "details": ["A flaw was found in Coturn, an open-source implementation of TURN and STUN servers. An authenticated TURN client can bypass the default loopback protection mechanism by using an IPv4-mapped IPv6 peer address. This allows the client to expose services that are intended to be accessible only from the local machine on the Coturn host through TURN relay traffic. This could lead to unauthorized access to internal services."], "mitigation": {"lang": "en:us", "value": "No action needed \u2014 the shipped coturn build (4.14.0) already contains the upstream fix."}, "name": "CVE-2026-53450", "public_date": "2026-07-10T18:05:06Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-53450\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-53450\nhttps://github.com/coturn/coturn/commit/b057acbebe721c8f2f202ddad5e16289e295c754\nhttps://github.com/coturn/coturn/security/advisories/GHSA-w4hf-cr3w-6h79"], "statement": "This flaw affects the community-maintained coturn TURN/STUN server as shipped in Fedora and EPEL. Red Hat does not ship coturn in any core Red Hat product. Fedora and EPEL currently ship coturn 4.14.0, which already includes the fix released in 4.13.0, so the shipped builds are not vulnerable to this loopback-protection bypass via IPv4-mapped IPv6 addresses.", "threat_severity": "Important"}

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