{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80212","assignerOrgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","state":"PUBLISHED","assignerShortName":"mitre","dateReserved":"2026-08-26T01:42:16.295Z","datePublished":"2026-08-27T14:15:04.403Z","dateUpdated":"2026-08-27T19:33:58.773Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","packageURL":"pkg:gem/resolv","product":"resolv","vendor":"Ruby","versions":[{"lessThan":"0.3.2","status":"affected","version":"0","versionType":"semver"},{"lessThan":"0.7.2","status":"affected","version":"0.4.0","versionType":"semver"}]}],"descriptions":[{"lang":"en","value":"An issue was discovered in the resolv gem before 0.7.2 for Ruby. Resolv::DNS::Resource.get_class, Resolv::DNS::Resource::Generic.create, and Resolv::DNS::SvcParam::Generic.create generate a new class for each unknown DNS resource record (type, class) pair, or each unknown SvcParamKey, encountered while decoding a response. Each generated class was permanently registered both as a constant on Resource (or SvcParam::Generic) and as an entry in a class-lookup hash (ClassHash), and thus the class remained reachable through that constant after the response was discarded. Type and class are each 16-bit values, and thus an attacker controlling DNS responses (a spoofed response, or a malicious or hijacked upstream DNS server) has roughly 2^32 distinct (type, class) pairs to choose from. A single response of a few hundred kilobytes carrying tens of thousands of distinct unknown types permanently grows process memory by tens of megabytes; repeated responses accumulate without bound and are never reclaimed by garbage collection, because the constant keeps each class alive. Any code path that calls Resolv::DNS::Message.decode on attacker-influenced DNS responses is affected. resolv is a default gem, and thus this is reachable from a plain Ruby installation without any additional dependency."}],"metrics":[{"cvssV3_1":{"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"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","description":"CWE-770 Allocation of Resources Without Limits or Throttling","lang":"en","type":"CWE"}]}],"providerMetadata":{"orgId":"8254265b-2729-46b6-b9e3-3dfca2d5bfca","shortName":"mitre","dateUpdated":"2026-08-27T14:15:04.403Z"},"references":[{"url":"https://github.com/ruby/resolv"},{"url":"https://www.ruby-lang.org/en/news/2026/08/27/multiple-vulnerabilities-in-resolv/"}],"x_generator":{"engine":"CVE-Request-form 0.0.1"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-27T19:33:50.602678Z","id":"CVE-2026-80212","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"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":"2026-08-27T19:33:58.773Z"}}]}}