{"id":"CVE-2026-40211","state":"PUBLISHED","title":"Denial of service via crafted DoH3 queries","description":"An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service.","publishedAt":"2026-06-25T12:23:55.585Z","updatedAt":"2026-06-25T13:45:02.430Z","severity":{"score":5.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","source":"OX"},"assigner":"OX","products":["PowerDNS DNSdist"],"affected":[{"vendor":"PowerDNS","product":"DNSdist","packageName":"dnsdist","defaultStatus":"unaffected","versions":[{"version":"1.9.0","status":"affected","lessThan":"1.9.15","versionType":"semver"},{"version":"2.0.0","status":"affected","lessThan":"2.0.7","versionType":"semver"}],"collectionURL":"https://repo.powerdns.com/","repo":"https://github.com/PowerDNS/pdns","modules":["DNS over HTTP3"],"programFiles":["dnsdist-crypto.cc"]}],"references":["https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html"],"weaknesses":["CWE-770"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/40xxx/CVE-2026-40211.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40211","state":"PUBLISHED","datePublished":"2026-06-25T12:23:55.585Z","dateUpdated":"2026-06-25T13:45:02.430Z","assignerShortName":"OX","assignerOrgId":"8ce71d90-2354-404b-a86e-bec2cc4e6981","dateReserved":"2026-04-10T07:11:39.060Z"},"containers":{"cna":{"title":"Denial of service via crafted DoH3 queries","descriptions":[{"lang":"en","value":"An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service."}],"affected":[{"vendor":"PowerDNS","product":"DNSdist","packageName":"dnsdist","defaultStatus":"unaffected","versions":[{"version":"1.9.0","status":"affected","lessThan":"1.9.15","versionType":"semver"},{"version":"2.0.0","status":"affected","lessThan":"2.0.7","versionType":"semver"}],"collectionURL":"https://repo.powerdns.com/","repo":"https://github.com/PowerDNS/pdns","modules":["DNS over HTTP3"],"programFiles":["dnsdist-crypto.cc"]}],"references":[{"url":"https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html"}],"metrics":[{"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}],"cvssV3_1":{"version":"3.1","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"LOW","baseSeverity":"MEDIUM","baseScore":5.3,"vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"}}],"problemTypes":[{"descriptions":[{"lang":"en","description":"Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"OX","orgId":"8ce71d90-2354-404b-a86e-bec2cc4e6981","dateUpdated":"2026-06-25T12:23:55.585Z"},"datePublic":"2026-06-24T22:00:00.000Z","credits":[{"lang":"en","value":"Mehtab Zafar","type":"finder"}],"source":{"discovery":"UNKNOWN"},"x_generator":{"engine":"Vulnogram 1.0.2"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-25T13:44:56.582604Z","id":"CVE-2026-40211","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","type":"CWE","lang":"en","description":"CWE-770 Allocation of Resources Without Limits or Throttling"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-25T13:45:02.430Z"}}]}}}