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{"bugzilla": {"description": "unbound: Unbound: Denial of Service via algorithmic complexity attacks on DNSSEC", "id": "2535057", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535057"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-770", "details": ["A flaw was found in Unbound. This vulnerability, termed 'ReTrap', allows a remote attacker to launch algorithmic complexity attacks on the Domain Name System Security Extensions (DNSSEC) validation process. By serving malicious zones or responses, an attacker can exploit various mechanisms, such as mismatched DNSKEY records, deeply nested domains, or excessive invalid NSEC records. Successful exploitation leads to a degradation of service, effectively causing a Denial of Service (DoS) for affected Unbound resolvers."], "name": "CVE-2026-85501", "package_state": [{"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-16T08:32:25Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-85501\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-85501\nhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-85501.txt"], "threat_severity": "Moderate"}

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