CVE-2026-84637
Calendar invitation attachments could launch local executables
CVE-2026-84637 is fixed in 134 products on 3 platforms, first by Mozilla Thunderbird 155.0, released August 28, 2026. It is not reported as exploited. Patch Radar priority: Urgent.
UrgentFixed on 3 platforms
CVSS
9.8
No vendor severity
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0063
50th percentile
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.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Windows apps | |||
| Mozilla Thunderbird (af) | 155.0 | Mozilla Thunderbird (af) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ar) | 155.0 | Mozilla Thunderbird (ar) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ast) | 155.0 | Mozilla Thunderbird (ast) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (be) | 155.0 | Mozilla Thunderbird (be) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (bg) | 155.0 | Mozilla Thunderbird (bg) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (br) | 155.0 | Mozilla Thunderbird (br) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ca) | 155.0 | Mozilla Thunderbird (ca) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (cak) | 155.0 | Mozilla Thunderbird (cak) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (cs) | 155.0 | Mozilla Thunderbird (cs) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (cy) | 155.0 | Mozilla Thunderbird (cy) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (da) | 155.0 | Mozilla Thunderbird (da) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (de) | 155.0 | Mozilla Thunderbird (de) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (dsb) | 155.0 | Mozilla Thunderbird (dsb) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (el) | 155.0 | Mozilla Thunderbird (el) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (en-CA) | 155.0 | Mozilla Thunderbird (en-CA) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (en-GB) | 155.0 | Mozilla Thunderbird (en-GB) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (en-US) | 155.0 | Mozilla Thunderbird (en-US) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (es-AR) | 155.0 | Mozilla Thunderbird (es-AR) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (es-ES) | 155.0 | Mozilla Thunderbird (es-ES) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (es-MX) | 155.0 | Mozilla Thunderbird (es-MX) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (et) | 155.0 | Mozilla Thunderbird (et) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (eu) | 155.0 | Mozilla Thunderbird (eu) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (fi) | 155.0 | Mozilla Thunderbird (fi) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (fr) | 155.0 | Mozilla Thunderbird (fr) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (fy-NL) | 155.0 | Mozilla Thunderbird (fy-NL) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ga-IE) | 155.0 | Mozilla Thunderbird (ga-IE) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (gd) | 155.0 | Mozilla Thunderbird (gd) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (gl) | 155.0 | Mozilla Thunderbird (gl) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (he) | 155.0 | Mozilla Thunderbird (he) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (hr) | 155.0 | Mozilla Thunderbird (hr) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (hsb) | 155.0 | Mozilla Thunderbird (hsb) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (hu) | 155.0 | Mozilla Thunderbird (hu) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (hy-AM) | 155.0 | Mozilla Thunderbird (hy-AM) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (id) | 155.0 | Mozilla Thunderbird (id) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (is) | 155.0 | Mozilla Thunderbird (is) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (it) | 155.0 | Mozilla Thunderbird (it) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ja) | 155.0 | Mozilla Thunderbird (ja) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ka) | 155.0 | Mozilla Thunderbird (ka) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (kab) | 155.0 | Mozilla Thunderbird (kab) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (kk) | 155.0 | Mozilla Thunderbird (kk) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ko) | 155.0 | Mozilla Thunderbird (ko) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (lt) | 155.0 | Mozilla Thunderbird (lt) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (lv) | 155.0 | Mozilla Thunderbird (lv) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ms) | 155.0 | Mozilla Thunderbird (ms) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (nb-NO) | 155.0 | Mozilla Thunderbird (nb-NO) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (nl) | 155.0 | Mozilla Thunderbird (nl) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (nn-NO) | 155.0 | Mozilla Thunderbird (nn-NO) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (pa-IN) | 155.0 | Mozilla Thunderbird (pa-IN) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (pl) | 155.0 | Mozilla Thunderbird (pl) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (pt-BR) | 155.0 | Mozilla Thunderbird (pt-BR) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (pt-PT) | 155.0 | Mozilla Thunderbird (pt-PT) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (rm) | 155.0 | Mozilla Thunderbird (rm) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ro) | 155.0 | Mozilla Thunderbird (ro) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (ru) | 155.0 | Mozilla Thunderbird (ru) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (sk) | 155.0 | Mozilla Thunderbird (sk) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (sl) | 155.0 | Mozilla Thunderbird (sl) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (sq) | 155.0 | Mozilla Thunderbird (sq) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (sr) | 155.0 | Mozilla Thunderbird (sr) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (sv-SE) | 155.0 | Mozilla Thunderbird (sv-SE) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (th) | 155.0 | Mozilla Thunderbird (th) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (tr) | 155.0 | Mozilla Thunderbird (tr) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (uk) | 155.0 | Mozilla Thunderbird (uk) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (uz) | 155.0 | Mozilla Thunderbird (uz) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (vi) | 155.0 | Mozilla Thunderbird (vi) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (zh-CN) | 155.0 | Mozilla Thunderbird (zh-CN) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird (zh-TW) | 155.0 | Mozilla Thunderbird (zh-TW) 155.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (af) | 153.2.0 | Mozilla Thunderbird ESR (af) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ar) | 153.2.0 | Mozilla Thunderbird ESR (ar) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ast) | 153.2.0 | Mozilla Thunderbird ESR (ast) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (be) | 153.2.0 | Mozilla Thunderbird ESR (be) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (bg) | 153.2.0 | Mozilla Thunderbird ESR (bg) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (br) | 153.2.0 | Mozilla Thunderbird ESR (br) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ca) | 153.2.0 | Mozilla Thunderbird ESR (ca) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (cak) | 153.2.0 | Mozilla Thunderbird ESR (cak) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (cs) | 153.2.0 | Mozilla Thunderbird ESR (cs) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (cy) | 153.2.0 | Mozilla Thunderbird ESR (cy) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (da) | 153.2.0 | Mozilla Thunderbird ESR (da) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (de) | 153.2.0 | Mozilla Thunderbird ESR (de) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (dsb) | 153.2.0 | Mozilla Thunderbird ESR (dsb) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (el) | 153.2.0 | Mozilla Thunderbird ESR (el) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (en-CA) | 153.2.0 | Mozilla Thunderbird ESR (en-CA) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (en-GB) | 153.2.0 | Mozilla Thunderbird ESR (en-GB) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (en-US) | 153.2.0 | Mozilla Thunderbird ESR (en-US) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (es-AR) | 153.2.0 | Mozilla Thunderbird ESR (es-AR) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (es-ES) | 153.2.0 | Mozilla Thunderbird ESR (es-ES) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (es-MX) | 153.2.0 | Mozilla Thunderbird ESR (es-MX) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (et) | 153.2.0 | Mozilla Thunderbird ESR (et) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (eu) | 153.2.0 | Mozilla Thunderbird ESR (eu) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (fi) | 153.2.0 | Mozilla Thunderbird ESR (fi) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (fr) | 153.2.0 | Mozilla Thunderbird ESR (fr) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (fy-NL) | 153.2.0 | Mozilla Thunderbird ESR (fy-NL) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ga-IE) | 153.2.0 | Mozilla Thunderbird ESR (ga-IE) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (gd) | 153.2.0 | Mozilla Thunderbird ESR (gd) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (gl) | 153.2.0 | Mozilla Thunderbird ESR (gl) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (he) | 153.2.0 | Mozilla Thunderbird ESR (he) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (hr) | 153.2.0 | Mozilla Thunderbird ESR (hr) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (hsb) | 153.2.0 | Mozilla Thunderbird ESR (hsb) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (hu) | 153.2.0 | Mozilla Thunderbird ESR (hu) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (hy-AM) | 153.2.0 | Mozilla Thunderbird ESR (hy-AM) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (id) | 153.2.0 | Mozilla Thunderbird ESR (id) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (is) | 153.2.0 | Mozilla Thunderbird ESR (is) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (it) | 153.2.0 | Mozilla Thunderbird ESR (it) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ja) | 153.2.0 | Mozilla Thunderbird ESR (ja) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ka) | 153.2.0 | Mozilla Thunderbird ESR (ka) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (kab) | 153.2.0 | Mozilla Thunderbird ESR (kab) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (kk) | 153.2.0 | Mozilla Thunderbird ESR (kk) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ko) | 153.2.0 | Mozilla Thunderbird ESR (ko) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (lt) | 153.2.0 | Mozilla Thunderbird ESR (lt) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (lv) | 153.2.0 | Mozilla Thunderbird ESR (lv) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ms) | 153.2.0 | Mozilla Thunderbird ESR (ms) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (nb-NO) | 153.2.0 | Mozilla Thunderbird ESR (nb-NO) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (nl) | 153.2.0 | Mozilla Thunderbird ESR (nl) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (nn-NO) | 153.2.0 | Mozilla Thunderbird ESR (nn-NO) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (pa-IN) | 153.2.0 | Mozilla Thunderbird ESR (pa-IN) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (pl) | 153.2.0 | Mozilla Thunderbird ESR (pl) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (pt-BR) | 153.2.0 | Mozilla Thunderbird ESR (pt-BR) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (pt-PT) | 153.2.0 | Mozilla Thunderbird ESR (pt-PT) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (rm) | 153.2.0 | Mozilla Thunderbird ESR (rm) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ro) | 153.2.0 | Mozilla Thunderbird ESR (ro) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (ru) | 153.2.0 | Mozilla Thunderbird ESR (ru) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (sk) | 153.2.0 | Mozilla Thunderbird ESR (sk) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (sl) | 153.2.0 | Mozilla Thunderbird ESR (sl) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (sq) | 153.2.0 | Mozilla Thunderbird ESR (sq) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (sr) | 153.2.0 | Mozilla Thunderbird ESR (sr) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (sv-SE) | 153.2.0 | Mozilla Thunderbird ESR (sv-SE) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (th) | 153.2.0 | Mozilla Thunderbird ESR (th) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (tr) | 153.2.0 | Mozilla Thunderbird ESR (tr) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (uk) | 153.2.0 | Mozilla Thunderbird ESR (uk) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (uz) | 153.2.0 | Mozilla Thunderbird ESR (uz) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (vi) | 153.2.0 | Mozilla Thunderbird ESR (vi) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (zh-CN) | 153.2.0 | Mozilla Thunderbird ESR (zh-CN) 153.2.0 | Sep 1, 2026 |
| Mozilla Thunderbird ESR (zh-TW) | 153.2.0 | Mozilla Thunderbird ESR (zh-TW) 153.2.0 | Sep 1, 2026 |
| macOS | |||
| Mozilla Thunderbird | 155.0 | Mozilla Thunderbird 155.0 | Aug 28, 2026 |
| Linux | |||
| MozillaThunderbird · sles 15.7 | 153.2.0-150400.13.3.1 | SUSE-SU-2026:4268-1 | Sep 18, 2026 |
Patch Radar data is free to use with attribution. Terms and how to credit it.
Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.