CVE-2026-77860

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{"bugzilla": {"description": "unbound: Unbound: Denial of Service via 'serve-expired' code path bypass", "id": "2535050", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535050"}, "csaw": false, "cvss3": {"cvss3_base_score": "3.7", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L", "status": "draft"}, "cwe": "CWE-911", "details": ["A flaw was found in Unbound. A remote attacker can exploit a vulnerability in the 'serve-expired' code path by sending specially crafted DNS queries. This manipulation causes a double decrement of a security counter, effectively bypassing a protection mechanism designed to limit pending queries. Consequently, an attacker can hold an arbitrary number of pending queries from a single source, leading to a Denial of Service (DoS) condition."], "name": "CVE-2026-77860", "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": "2026-09-16T08:29:23Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-77860\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-77860\nhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-77860.txt"], "threat_severity": "Low"}

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