{"schema":"threatline.record/2","record":{"id":"CVE-2026-80212","aliases":[],"summary":"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 ","details":"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.","categories":["Runtimes & languages"],"product":"resolv","vendor":"Ruby","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-80212","source_modified_at":"2026-08-27T19:33:58.773Z","fetched_at":"2026-10-24T23:06:24.700873Z","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"}],"defaultStatus":"unaffected"}],"fixed_versions":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-80212","source_modified_at":"2026-08-27T19:33:58.773Z","fetched_at":"2026-10-24T23:06:24.700873Z","package":{"name":"resolv","ecosystem":null},"version":"0.3.2","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-80212","source_modified_at":"2026-08-27T19:33:58.773Z","fetched_at":"2026-10-24T23:06:24.700873Z","package":{"name":"resolv","ecosystem":null},"version":"0.7.2","basis":"first unaffected version stated in the CVE record"}],"cvss":7.5,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00401,"percentile":0.33256,"score_date":"2026-10-24"},"published_at":"2026-08-27T14:15:04.403Z","modified_at":"2026-08-27T19:33:58.773Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-80212","fetched_at":"2026-10-24T23:06:24.700873Z","source_modified_at":"2026-08-27T19:33:58.773Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-80212","fetched_at":"2026-10-24T23:06:24.700873Z","source_modified_at":"2026-10-24"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/ruby/resolv"},{"source":"CVE List","url":"https://www.ruby-lang.org/en/news/2026/08/27/multiple-vulnerabilities-in-resolv/"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-08-27T19:33:50.602678Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"vendor and product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-08-27T19:33:58.773Z","content_hash":"30c88b97ed20b7a5069da12aa77319145f3a8461c0eaa10bf736dd1ef981d05e"}}