{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-84639", "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "state": "PUBLISHED", "assignerShortName": "mozilla", "dateReserved": "2026-09-01T21:33:05.937Z", "datePublished": "2026-09-01T21:33:06.251Z", "dateUpdated": "2026-09-01T21:44:15.369Z"}, "containers": {"cna": {"affected": [{"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"status": "unaffected", "version": "140.15", "lessThanOrEqual": "140.*", "versionType": "rpm"}, {"status": "unaffected", "version": "153.2", "lessThanOrEqual": "153.*", "versionType": "rpm"}, {"status": "unaffected", "version": "155", "lessThanOrEqual": "*", "versionType": "rpm"}]}], "descriptions": [{"lang": "en", "value": "Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.", "supportingMedia": [{"type": "text/html", "base64": false, "value": "Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."}]}], "title": "Uninitialized memory in MIME parsing", "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2061087"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"}], "credits": [{"lang": "en", "value": "Ramesh Adhikari, Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India)"}], "providerMetadata": {"orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe", "shortName": "mozilla", "dateUpdated": "2026-09-01T21:44:15.369Z"}}}}

{}

{"affected": [{"affectedData": [{"product": "Thunderbird", "vendor": "Mozilla", "versions": [{"lessThanOrEqual": "140.*", "status": "unaffected", "version": "140.15", "versionType": "rpm"}, {"lessThanOrEqual": "153.*", "status": "unaffected", "version": "153.2", "versionType": "rpm"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "155", "versionType": "rpm"}]}], "source": "security@mozilla.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."}], "id": "CVE-2026-84639", "lastModified": "2026-09-01T22:17:19.700", "metrics": {}, "published": "2026-09-01T22:17:19.700", "references": [{"source": "security@mozilla.org", "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2061087"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"}, {"source": "security@mozilla.org", "url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"}], "sourceIdentifier": "security@mozilla.org", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[140.15,141.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[153.2,154.0.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[155,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}], "created": "2026-09-02T00:00:06.058975+00:00", "updated": "2026-09-02T00:30:04.118426+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$thunderbird"]}