EUVD Vulnerability Catalog

EUVD-2026-69703

Severity: CRITICAL Base Score: 9.8 CVSS Version: 3.1

Vulnerability 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.

CVSS Vector Analysis

Below is the complete, human-readable breakdown of the CVSS metric string: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

▪ Attack Vector (AV): Network

▪ Attack Complexity (AC): Low

▪ Privileges Required (PR): None

▪ User Interaction (UI): None

▪ Scope (S): Unchanged

▪ Confidentiality Impact (C): High

▪ Integrity Impact (I): High

▪ Availability Impact (A): High

References & Advisory Links

Metadata Profile

Database Authority

European Union Agency for Cybersecurity (ENISA) EUVD

Assigner

mozilla

EPSS Probability

Known Aliases

GHSA-3q74-4f83-x4rj CVE-2026-84637

Published On

2026-09-01

Last Updated

2026-09-02