CVE-2026-81634

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{"bugzilla": {"description": "unbound: Unbound: Heap buffer overflow via malicious DNSSEC response", "id": "2535054", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535054"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-120", "details": ["A flaw was found in Unbound. This vulnerability allows a remote attacker to cause a heap buffer overflow during the processing of DNSSEC responses. By sending a specially crafted DNSSEC response, a malicious server or an attacker tampering with network traffic can trigger this flaw. This could lead to a denial of service, making the Unbound service unavailable."], "name": "CVE-2026-81634", "package_state": [{"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift/ose-rhel-coreos-8", "product_name": "Red Hat OpenShift Container Platform 4"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Affected", "package_name": "openshift/ose-rhel-coreos-9", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-09-16T08:30:15Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-81634\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-81634\nhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-81634.txt"], "threat_severity": "Important"}

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