VULNERABILITY INTELLIGENCE

CVE-2026-84637

CVSS score9.8 CRITICAL
EPSS probability0.63%
CISA KEVNot currently listed
Published2026-09-01
Last modified2026-09-03
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

Weakness classification

  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-434

Primary references