CVE-2026-84637: Vulnerability in Mozilla Thunderbird
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.
CVE-2026-84637: Vulnerability in Mozilla Thunderbird
Description
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.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-01T21:25:08.170Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-78/","vendor":"Mozilla"}]
Threat ID: 6a9745b0acd9273b493a43b0
Added to database: 09/01/2026, 21:37:52 UTC
Last updated: 09/01/2026, 22:52:29 UTC
Views: 5
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