{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-84142","assignerOrgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","state":"PUBLISHED","assignerShortName":"mozilla","dateReserved":"2026-09-01T07:26:00.760Z","datePublished":"2026-09-01T12:19:09.109Z","dateUpdated":"2026-09-03T17:23:40.751Z"},"containers":{"cna":{"affected":[{"product":"Firefox","vendor":"Mozilla","versions":[{"status":"unaffected","version":"155","lessThanOrEqual":"*","versionType":"rpm"}]},{"product":"Thunderbird","vendor":"Mozilla","versions":[{"status":"unaffected","version":"155","lessThanOrEqual":"*","versionType":"rpm"}]}],"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.","supportingMedia":[{"type":"text/html","base64":false,"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."}]}],"title":"Internally found bugs fixed in Thunderbird 155","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/"}],"credits":[{"lang":"en","value":"Alexandre Poirot, Christian Holler, Sebastian Hengst and the Mozilla Fuzzing Team"}],"providerMetadata":{"orgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","shortName":"mozilla","dateUpdated":"2026-09-01T21:33:04.550Z"}},"adp":[{"problemTypes":[{"descriptions":[{"type":"CWE","cweId":"CWE-200","lang":"en","description":"CWE-200 Exposure of Sensitive Information to an Unauthorized Actor"}]}],"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"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-03T17:23:40.751Z"}}]}}