vulnerability

MFSA2021-26 Thunderbird: Security Vulnerabilities fixed in Thunderbird 78.11 (CVE-2021-29964)

Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:P)
Published
Jun 3, 2021
Added
Jun 4, 2021
Modified
Aug 12, 2025

Description

A locally-installed hostile program could send `WM_COPYDATA` messages that Firefox would process incorrectly, leading to an out-of-bounds read. *This bug only affects Firefox on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 78.11, Firefox < 89, and Firefox ESR < 78.11.

Solution

mozilla-thunderbird-upgrade-78_11
Title
NEW

Explore Exposure Command

Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.