CVE-2026-4891

{"id": "CVE-2026-4891", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-4891", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-05-11T18:27:33.459839Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "NONE", "confidentialityImpact": "LOW"}, "impactScore": 1.4, "exploitabilityScore": 3.9}, {"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 3.9}]}, "affected": [{"source": "cret@cert.org", "affectedData": [{"vendor": "dnsmasq", "product": "dnsmasq", "versions": [{"status": "affected", "version": "0", "lessThan": "2.92rel2", "versionType": "custom"}]}]}, {"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "affectedData": [{"cpes": ["cpe:/o:redhat:enterprise_linux:10.2"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "versions": [{"status": "unaffected", "version": "0:2.90-7.el10_2", "lessThan": "*", "versionType": "rpm"}], "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:enterprise_linux:8"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8", "versions": [{"status": "unaffected", "version": "0:2.79-36.el8_10", "lessThan": "*", "versionType": "rpm"}], "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:enterprise_linux:9"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "versions": [{"status": "unaffected", "version": "0:2.85-18.el9_8.1", "lessThan": "*", "versionType": "rpm"}], "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:rhel_eus:9.6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9.6 Extended Update Support", "versions": [{"status": "unaffected", "version": "0:2.85-17.el9_6.1", "lessThan": "*", "versionType": "rpm"}], "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/a:redhat:openshift:4.19::el9"], "vendor": "Red Hat", "product": "Red Hat OpenShift Container Platform 4.19", "versions": [{"status": "unaffected", "version": "4.19.9.6.202607151909-0", "lessThan": "*", "versionType": "rpm"}], "packageName": "rhcos", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 6", "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:7"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 7", "packageName": "dnsmasq", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "affected"}]}], "published": "2026-05-11T18:16:41.380", "references": [{"url": "https://github.com/NixOS/nixpkgs/pull/519082", "source": "cret@cert.org"}, {"url": "https://github.com/NixOS/nixpkgs/pull/519093", "source": "cret@cert.org"}, {"url": "https://github.com/pi-hole/FTL/releases/tag/v6.6.2", "source": "cret@cert.org"}, {"url": "https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html", "source": "cret@cert.org"}, {"url": "https://thekelleys.org.uk/dnsmasq/CVE/", "source": "cret@cert.org"}, {"url": "https://www.kb.cert.org/vuls/id/471747", "source": "cret@cert.org"}, {"url": "https://access.redhat.com/errata/RHSA-2026:19158", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:19373", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:20589", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:34508", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/errata/RHSA-2026:40762", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4891", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2458517", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}, {"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4891.json", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c", "description": [{"lang": "en", "value": "CWE-125"}]}], "descriptions": [{"lang": "en", "value": "A heap-based out-of-bounds read vulnerability in the DNSSEC validation of dnsmasq allows remote attackers to cause a denial of service via a crafted DNS packet."}], "lastModified": "2026-08-25T13:19:21.527", "sourceIdentifier": "cret@cert.org"}