{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42256","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-04-26T11:53:27.704Z","datePublished":"2026-05-09T19:38:33.106Z","dateUpdated":"2026-05-11T17:04:42.562Z"},"containers":{"cna":{"title":"net-imap: Denial of service via high iteration count for `SCRAM-*` authentication","problemTypes":[{"descriptions":[{"cweId":"CWE-1322","lang":"en","description":"CWE-1322: Use of Blocking Code in Single-threaded, Non-blocking Context","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"references":[{"name":"https://github.com/ruby/net-imap/security/advisories/GHSA-87pf-fpwv-p7m7","tags":["x_refsource_CONFIRM"],"url":"https://github.com/ruby/net-imap/security/advisories/GHSA-87pf-fpwv-p7m7"},{"name":"https://github.com/ruby/net-imap/commit/158d0b505074397cdb5ceb58935e42dd2bcfa612","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/commit/158d0b505074397cdb5ceb58935e42dd2bcfa612"},{"name":"https://github.com/ruby/net-imap/commit/808001bc45c06f7297a7e96d341279e041a7f7f4","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/commit/808001bc45c06f7297a7e96d341279e041a7f7f4"},{"name":"https://github.com/ruby/net-imap/commit/99f59eab6064955a23debd95410263ad144df758","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/commit/99f59eab6064955a23debd95410263ad144df758"},{"name":"https://github.com/ruby/net-imap/releases/tag/v0.4.24","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/releases/tag/v0.4.24"},{"name":"https://github.com/ruby/net-imap/releases/tag/v0.5.14","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/releases/tag/v0.5.14"},{"name":"https://github.com/ruby/net-imap/releases/tag/v0.6.4","tags":["x_refsource_MISC"],"url":"https://github.com/ruby/net-imap/releases/tag/v0.6.4"}],"affected":[{"vendor":"ruby","product":"net-imap","versions":[{"version":">= 0.4.0, < 0.4.24","status":"affected"},{"version":">= 0.5.0, < 0.5.14","status":"affected"},{"version":">= 0.6.0, < 0.6.4","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-05-09T19:38:33.106Z"},"descriptions":[{"lang":"en","value":"Net::IMAP implements Internet Message Access Protocol (IMAP) client functionality in Ruby. From versions 0.4.0 to before 0.4.24, 0.5.0 to before 0.5.14, and 0.6.0 to before 0.6.4, when authenticating a connection with SCRAM-SHA1 or SCRAM-SHA256, a hostile server can perform a computational denial-of-service attack on the client process by sending a big iteration count value. This issue has been patched in versions 0.4.24, 0.5.14, and 0.6.4."}],"source":{"advisory":"GHSA-87pf-fpwv-p7m7","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-11T17:04:26.784816Z","id":"CVE-2026-42256","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":"2026-05-11T17:04:42.562Z"}}]}}