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{"affected_release": [{"advisory": "RHSA-2026:43588", "cpe": "cpe:/a:redhat:hummingbird:1", "package": "unbound-main-1.25.2-0.1.hum1", "product_name": "Red Hat Hardened Images", "release_date": "2026-07-22T00:00:00Z"}], "bugzilla": {"description": "unbound: libngtcp2: Unbound: Denial of Service via assertion failure in DNS-over-QUIC environments", "id": "2506128", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2506128"}, "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": "verified"}, "cwe": "CWE-617", "details": ["A flaw was found in Unbound. Under heavy DNS-over-QUIC (DoQ) traffic, a timing discrepancy in Unbound\u2019s libngtcp2 library can trigger an assertion failure. This causes the server to crash unexpectedly, resulting in a denial of service (DoS)."], "mitigation": {"lang": "en:us", "value": "Disable DNS-over-QUIC (DoQ) by removing or commenting out any quic-port directives in your unbound.conf file.\nRestart the unbound service for the changes to take effect and prevent potential assertion crashes."}, "name": "CVE-2026-14586", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "unbound", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "unbound", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "unbound", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "unbound", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Fix deferred", "package_name": "unbound", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:openshift:4", "fix_state": "Fix deferred", "package_name": "rhcos", "product_name": "Red Hat OpenShift Container Platform 4"}], "public_date": "2026-07-22T13:03:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-14586\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-14586\nhttps://www.nlnetlabs.nl/downloads/unbound/CVE-2026-14586.txt"], "statement": "Moderate: This Unbound vulnerability, leading to a denial of service, is contingent on the resolver being compiled with DNS-over-QUIC (DoQ) support and having a `quic-port` configured. The flaw manifests under high concurrency and network pressure due to a timing discrepancy in the `libngtcp2` library. Red Hat deployments not utilizing DoQ or without the `quic-port` enabled are not affected.", "threat_severity": "Moderate"}