CVE-2026-81563

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{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "BIND 9", "vendor": "ISC", "versions": [{"lessThanOrEqual": "9.18.50", "status": "affected", "version": "9.18.0", "versionType": "custom"}, {"lessThanOrEqual": "9.20.27", "status": "affected", "version": "9.20.0", "versionType": "custom"}, {"lessThanOrEqual": "9.21.25", "status": "affected", "version": "9.21.0", "versionType": "custom"}, {"lessThanOrEqual": "9.18.50-S1", "status": "affected", "version": "9.18.11-S1", "versionType": "custom"}, {"lessThanOrEqual": "9.20.27-S1", "status": "affected", "version": "9.20.9-S1", "versionType": "custom"}]}], "source": "security-officer@isc.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups.\nThis issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1."}, {"lang": "es", "value": "Un resolvedor BIND que encuentre un registro SVCB/HTTPS AliasMode que haga referencia a 14 o m\u00e1s registros SVCB/HTTPS ServiceMode puede no liberar correctamente los recursos internos. Si esto ocurre repetidamente, el agotamiento de recursos impedir\u00e1 eventualmente que el resolvedor realice nuevas b\u00fasquedas recursivas. \\nEste problema afecta a BIND?9 desde la versi\u00f3n?9.18.0 hasta la versi\u00f3n?9.18.50 incluida, desde la versi\u00f3n?9.20.0 hasta la versi\u00f3n?9.20.27 incluida, desde la versi\u00f3n?9.21.0 hasta la versi\u00f3n?9.21.25 incluida, desde la versi\u00f3n?9.18.11?S1 hasta la versi\u00f3n?9.18.50?S1 incluida, y desde la versi\u00f3n?9.20.9?S1 hasta la versi\u00f3n?9.20.27?S1 incluida."}], "id": "CVE-2026-81563", "lastModified": "2026-10-26T20:10:00.160", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-officer@isc.org", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-81563", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-17T17:47:13.244761Z", "version": "2.0.3"}}]}, "published": "2026-09-16T14:17:10.543", "references": [{"source": "security-officer@isc.org", "url": "https://downloads.isc.org/isc/bind9/9.20.29"}, {"source": "security-officer@isc.org", "url": "https://downloads.isc.org/isc/bind9/9.21.26"}, {"source": "security-officer@isc.org", "url": "https://kb.isc.org/docs/cve-2026-81563"}], "sourceIdentifier": "security-officer@isc.org", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-401"}], "source": "security-officer@isc.org", "type": "Secondary"}]}

{"bugzilla": {"description": "bind: BIND resolver: Denial of Service due to resource exhaustion in SVCB/HTTPS AliasMode processing", "id": "2535461", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2535461"}, "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-772", "details": ["A flaw was found in the BIND resolver. A remote attacker could exploit a vulnerability in the processing of SVCB/HTTPS AliasMode records that reference numerous ServiceMode records. This could lead to the resolver failing to properly release internal resources, causing resource exhaustion. Repeated exploitation would prevent the resolver from performing new recursive lookups, resulting in a Denial of Service (DoS)."], "mitigation": {"lang": "en:us", "value": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability."}, "name": "CVE-2026-81563", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "bind", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "bind", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "bind", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "bind", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "bind9.16", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "bind", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "bind9.18", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "dhcp", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/a:redhat:hummingbird:1", "fix_state": "Affected", "package_name": "bind", "product_name": "Red Hat Hardened Images"}, {"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": "2026-09-16T14:00:04Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-81563\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-81563\nhttps://downloads.isc.org/isc/bind9/9.20.29\nhttps://downloads.isc.org/isc/bind9/9.21.26\nhttps://kb.isc.org/docs/cve-2026-81563"], "statement": "This Important denial of service vulnerability affects BIND resolvers, which are critical for DNS resolution in Red Hat environments. Repeated processing of specially crafted SVCB/HTTPS AliasMode records can exhaust internal resources, ultimately preventing the resolver from performing new recursive lookups and disrupting service availability.", "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": null}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "product": "bind", "vendor": "isc"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[9.18.0,9.18.50]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[9.20.0,9.20.27]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[9.21.0,9.21.25]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[9.18.11-S1,9.18.50-S1]"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[9.20.9-S1,9.20.27-S1]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "BIND 9", "source": "cna", "vendor": "ISC"}, "product": "bind_9", "vendor": "isc"}], "created": "2026-09-17T02:15:08.107252+00:00", "updated": "2026-09-18T04:00:03.418931+00:00", "vendors": ["isc", "isc$PRODUCT$bind", "isc$PRODUCT$bind_9"]}