{"id":"CVE-2026-84637","aliases":[],"url":"https://o3.security/vulnerability/CVE-2026-84637","summary":"Malicious calendar invitations could use file URI attachments to launch local or network-hosted executables on Windows, bypassing Thunderbird's normal executable attachment protections.…","details":"Malicious calendar invitations could use file URI attachments to launch local or network-hosted executables on Windows, bypassing Thunderbird's normal executable attachment protections. With the new invitation display enabled, the attachment could also appear under a misleading filename. This vulnerability was fixed in Thunderbird 154 and Thunderbird 153.2.","published":"2026-09-01T22:17:19.597","modified":"2026-09-03T19:02:08.287","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":"WEB","url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2043878"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2026-78/"},{"type":"ADVISORY","url":"https://www.mozilla.org/security/advisories/mfsa2026-88/"}],"provenance":{"sources":["OSV.dev","NVD","FIRST.org (EPSS)"],"lastVerified":"2026-09-03T19:02:08.287"}}