{"id":"CVE-2026-84142","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-84142","summary":"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…","details":"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.","published":"2026-09-01T13:20:08.337","modified":"2026-09-03T16:00:08.613","cvss":{"score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":null,"references":[{"type":"REPORT","url":"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2029421%2C2040889%2C2045313%2C2045435%2C2053578%2C2058621%2C2058626"},{"type":"REPORT","url":"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048796%2C2053150%2C2057356"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2026-82/"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2026-86/"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-09-03T16:00:08.613"}}