MFSA2026-20: Security Vulnerabilities fixed in Firefox 149
Published Mar 24, 2026
·Updated
Security Vulnerabilities fixed in Firefox 149
Affected Software
1 affected componentFixes available
Mozilla Firefox<149
149
Event History
Mar 24, 2026
Advisory Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Child vulnerabilities
Contains the following vulnerabilities.
- CVE-2026-4684
- CVE-2026-4685
- CVE-2026-4686
- CVE-2026-4687
- CVE-2026-4688
- CVE-2026-4689
- CVE-2026-4690
- CVE-2026-4691
- CVE-2026-4692
- CVE-2026-4693
- CVE-2026-4694
- CVE-2026-4695
- CVE-2026-4696
- CVE-2026-4697
- CVE-2026-4698
- CVE-2026-4699
- CVE-2026-4700
- CVE-2026-4701
- CVE-2026-4722
- CVE-2026-4702
- CVE-2026-4723
- CVE-2026-4724
- CVE-2026-4704
- CVE-2026-4705
- CVE-2026-4706
- CVE-2026-4707
- CVE-2026-4708
- CVE-2026-4709
- CVE-2026-4710
- CVE-2026-4711
- CVE-2026-4725
- CVE-2026-4712
- CVE-2026-4713
- CVE-2026-4714
- CVE-2026-4715
- CVE-2026-4716
- CVE-2026-4717
- CVE-2026-4726
- CVE-2025-59375
- CVE-2026-4727
- CVE-2026-4728
- CVE-2026-4718
- CVE-2026-4719
- CVE-2026-4720
- CVE-2026-4729
- CVE-2026-4721
Frequently Asked Questions
1
What is the severity of MFSA2026-20?
The severity of MFSA2026-20 is classified as high due to the risks involved with the identified vulnerabilities in Firefox 149.
2
How do I fix MFSA2026-20?
To fix MFSA2026-20, update your Firefox browser to version 149 or later.
3
What types of vulnerabilities are addressed in MFSA2026-20?
MFSA2026-20 addresses multiple security vulnerabilities that could potentially allow for arbitrary code execution and information disclosure.
4
Are there any workarounds for MFSA2026-20?
There are no known workarounds for MFSA2026-20; updating to the latest version is the recommended solution.
5
Is my version of Firefox affected by MFSA2026-20?
If you are using Firefox version 149 or earlier, your version is affected by MFSA2026-20.