CVE-2026-78227

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{"bugzilla": {"description": "unbound: Unbound: Denial of Service via use-after-free in DoQ stream output buffer", "id": "2535052", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535052"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in Unbound. This vulnerability occurs in the DNS-over-QUIC (DoQ) stream output buffer when a client sends a RESET_STREAM, causing the output buffer to be freed while retransmission entries still point to it. A remote attacker, by querying Unbound over DoQ, withholding acknowledgments, and sending a RESET_STREAM, can trigger this flaw. This leads to retransmissions against freed memory, ultimately resulting in a denial of service due to an abnormal server exit."], "name": "CVE-2026-78227", "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": "2026-09-16T08:29:52Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-78227\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-78227\nhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-78227.txt"], "threat_severity": "Moderate"}

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