{"schemaVersion":3,"id":"USN-8478-1","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"ruby2.7, ruby3.0, ruby3.2, ruby3.3 vulnerabilities\n\nIt was discovered that Ruby's Net::IMAP library did not properly verify\nthat TLS encryption was started after issuing a STARTTLS command. A remote\nattacker could use this to perform a machine-in-the-middle attack and silently\nbypass TLS encryption. (CVE-2026-42246)\n\nIt was discovered that Ruby's Net::IMAP library did not validate\nstring arguments passed to certain commands. A remote attacker could use\nthis to inject arbitrary IMAP commands. (CVE-2026-42257)\n\nIt was discovered that Ruby's Net::IMAP library was vulnerable to a\ndenial of service attack when authenticating with SCRAM-SHA1 or\nSCRAM-SHA256. A hostile server could send a very large iteration count\nvalue to cause excessive computation in the client. This issue only\naffected ruby3.3. (CVE-2026-42256)","dates":{"published":"2025-06-29T09:15:31.000Z","modified":"2026-06-30T18:17:38.194Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":null,"severity":"unknown","version":null,"versionLabel":null,"source":null,"vector":null,"computed":false,"selection":"none"},"metrics":[]},"epss":{"probability":null,"percentile":null,"severity":"unknown","asOf":null,"change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[],"last30":[]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[],"affected":[{"vendor":"ubuntu","product":"ruby2.7","name":"ruby2.7","label":"ruby2.7","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/ruby2.7","purlType":"deb","versions":[{"text":"< 2.7.0-5ubuntu1.18+esm5","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 2.7.0-5ubuntu1.18+esm5","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"ruby3.0","name":"ruby3.0","label":"ruby3.0","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/ruby3.0","purlType":"deb","versions":[{"text":"< 3.0.2-7ubuntu2.13","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 3.0.2-7ubuntu2.13","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"ruby3.2","name":"ruby3.2","label":"ruby3.2","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/ruby3.2","purlType":"deb","versions":[{"text":"< 3.2.3-1ubuntu0.24.04.8","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 3.2.3-1ubuntu0.24.04.8","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"ruby3.3","name":"ruby3.3","label":"ruby3.3","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/ruby3.3","purlType":"deb","versions":[{"text":"< 3.3.8-2ubuntu3.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 3.3.8-2ubuntu3.1","eol":null,"hubHref":null}],"affectedCount":4,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://ubuntu.com/security/notices/USN-8478-1","label":"ubuntu.com/security/notices/USN-8478-1","hostname":"ubuntu.com","tags":["Advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-42246","label":"ubuntu.com/security/CVE-2026-42246","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://ubuntu.com/security/CVE-2026-42256","label":"ubuntu.com/security/CVE-2026-42256","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://ubuntu.com/security/CVE-2026-42257","label":"ubuntu.com/security/CVE-2026-42257","hostname":"ubuntu.com","tags":["REPORT"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":["CVE-2026-42246","CVE-2026-42256","CVE-2026-42257"]},"timeline":[{"kind":"published","date":"2025-06-29T09:15:31.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-06-30T18:17:38.194Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":0,"level":"minimal","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T04:04:01.126Z","stale":false,"partial":false}}