vulnerability
MFSA2021-24 Firefox: Security Vulnerabilities fixed in Firefox ESR 78.11 (CVE-2021-29964)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 6 | (AV:N/AC:M/Au:N/C:P/I:N/A:P) | Jun 1, 2021 | Jun 2, 2021 | Aug 11, 2025 |
Severity
6
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:P)
Published
Jun 1, 2021
Added
Jun 2, 2021
Modified
Aug 11, 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-firefox-esr-upgrade-78_11
NEW
Explore Exposure Command
Confidently identify and prioritize exposures from endpoint to cloud with full attack surface visibility and threat-aware risk context.