{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-4891", "assignerOrgId": "37e5125f-f79b-445b-8fad-9564f167944b", "state": "PUBLISHED", "assignerShortName": "certcc", "dateReserved": "2026-03-26T13:07:05.406Z", "datePublished": "2026-05-11T16:47:33.202Z", "dateUpdated": "2026-05-11T18:27:52.738Z"}, "containers": {"cna": {"title": "CVE-2026-4891", "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."}], "source": {"discovery": "UNKNOWN"}, "affected": [{"vendor": "dnsmasq", "product": "dnsmasq", "versions": [{"status": "affected", "version": "2.92rel2"}]}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "CWE-125: Out-of-bounds Read"}]}], "references": [{"url": "https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2026q2/018471.html"}, {"url": "https://www.kb.cert.org/vuls/id/471747"}, {"url": "https://thekelleys.org.uk/dnsmasq/CVE/"}, {"url": "https://github.com/NixOS/nixpkgs/pull/519082"}, {"url": "https://github.com/NixOS/nixpkgs/pull/519093"}], "x_generator": {"engine": "VINCE 3.0.39", "env": "prod", "origin": "https://cveawg.mitre.org/api/cve/CVE-2026-4891"}, "providerMetadata": {"orgId": "37e5125f-f79b-445b-8fad-9564f167944b", "shortName": "certcc", "dateUpdated": "2026-05-11T18:27:52.738Z"}}, "adp": [{"metrics": [{"cvssV3_1": {"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"}}, {"other": {"type": "ssvc", "content": {"timestamp": "2026-05-11T18:27:33.459839Z", "id": "CVE-2026-4891", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-05-11T18:27:36.545Z"}}]}}

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{"cveTags": [], "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."}], "id": "CVE-2026-4891", "lastModified": "2026-05-11T18:16:41.380", "metrics": {}, "published": "2026-05-11T18:16:41.380", "references": [{"source": "cret@cert.org", "url": "https://thekelleys.org.uk/dnsmasq/"}, {"source": "cret@cert.org", "url": "https://www.kb.cert.org/vuls/id/471747"}], "sourceIdentifier": "cret@cert.org", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "2.93"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "dnsmasq", "source": "cna", "vendor": "dnsmasq"}, "product": "dnsmasq", "vendor": "dnsmasq"}], "created": "2026-05-11T18:45:25.408702+00:00", "title": "Heap OOB Read in dnsmasq DNSSEC Validation Leading to DNS DoS", "updated": "2026-05-11T18:45:25.663959+00:00", "vendors": ["dnsmasq", "dnsmasq$PRODUCT$dnsmasq"], "weaknesses": ["CWE-125"]}