vulnerability
MFSA2026-20 Firefox: Security Vulnerabilities fixed in Firefox 149 (CVE-2026-4699)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:N/I:N/A:C) | Mar 24, 2026 | Mar 27, 2026 | Apr 15, 2026 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:C)
Published
Mar 24, 2026
Added
Mar 27, 2026
Modified
Apr 15, 2026
Description
Incorrect boundary conditions in the Layout: Text and Fonts component. This vulnerability was fixed in Firefox 149, Firefox ESR 115.34, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
Solution
mozilla-firefox-upgrade-149_0
Rapid7 Labs
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