{"id":"CVE-2026-84142","state":"PUBLISHED","title":"Internally found bugs fixed in Thunderbird 155","description":"Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155.","publishedAt":"2026-09-01T12:19:09.109Z","updatedAt":"2026-09-03T17:23:40.751Z","severity":{"score":9.8,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"CISA-ADP"},"assigner":"mozilla","products":["Mozilla Firefox","Mozilla Thunderbird"],"affected":[{"vendor":"Mozilla","product":"Firefox","versions":[{"version":"155","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]},{"vendor":"Mozilla","product":"Thunderbird","versions":[{"version":"155","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]}],"references":["https://bugzilla.mozilla.org/buglist.cgi?bug_id=2029421%2C2040889%2C2045313%2C2045435%2C2053578%2C2058621%2C2058626","https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048796%2C2053150%2C2057356","https://www.mozilla.org/security/advisories/mfsa2026-82/","https://www.mozilla.org/security/advisories/mfsa2026-86/"],"weaknesses":["CWE-200"],"ingestedAt":"2026-10-29T20:13:15.269Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/84xxx/CVE-2026-84142.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-84142","state":"PUBLISHED","datePublished":"2026-09-01T12:19:09.109Z","dateUpdated":"2026-09-03T17:23:40.751Z","assignerShortName":"mozilla","assignerOrgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","dateReserved":"2026-09-01T07:26:00.760Z"},"containers":{"cna":{"title":"Internally found bugs fixed in Thunderbird 155","descriptions":[{"lang":"en","value":"Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155."}],"affected":[{"vendor":"Mozilla","product":"Firefox","versions":[{"version":"155","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]},{"vendor":"Mozilla","product":"Thunderbird","versions":[{"version":"155","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]}],"references":[{"url":"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2029421%2C2040889%2C2045313%2C2045435%2C2053578%2C2058621%2C2058626","name":"Moderate Severity internally found bugs fixed in Thunderbird 155"},{"url":"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048796%2C2053150%2C2057356","name":"Low Severity internally found bugs fixed in Thunderbird 155"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-82/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-86/"}],"providerMetadata":{"shortName":"mozilla","orgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","dateUpdated":"2026-09-01T21:33:04.550Z"},"credits":[{"lang":"en","value":"Alexandre Poirot, Christian Holler, Sebastian Hengst and the Mozilla Fuzzing Team"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":9.8,"attackVector":"NETWORK","baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","integrityImpact":"HIGH","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-03T17:13:22.840270Z","id":"CVE-2026-84142","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-200","type":"CWE","lang":"en","description":"CWE-200 Exposure of Sensitive Information to an Unauthorized Actor"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-03T17:23:40.751Z"}}]}}}