MFSA2026-21: Security Vulnerabilities fixed in Firefox ESR 115.34
Published Mar 24, 2026
·Updated
Security Vulnerabilities fixed in Firefox ESR 115.34
Affected Software
1 affected componentFixes available
Mozilla Firefox ESR<115.34
115.34
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.
Frequently Asked Questions
1
What is the severity of MFSA2026-21?
The severity level of MFSA2026-21 is considered to be critical.
2
How do I fix MFSA2026-21?
To fix MFSA2026-21, update Firefox ESR to version 115.34 or later.
3
What vulnerabilities are addressed in MFSA2026-21?
MFSA2026-21 addresses multiple security vulnerabilities that could potentially allow for exploitation.
4
Who is affected by MFSA2026-21?
Users running Firefox ESR versions prior to 115.34 are affected by MFSA2026-21.
5
Is there an impact on previous versions of Firefox ESR due to MFSA2026-21?
Yes, previous versions of Firefox ESR prior to 115.34 may expose users to security risks.