MFSA2026-48: Security Vulnerabilities fixed in Firefox ESR 140.11
Published May 19, 2026
·Updated
Security Vulnerabilities fixed in Firefox ESR 140.11
Affected Software
1 affected componentFixes available
Mozilla Firefox ESR<140.11
140.11
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 140.11 - Upgrade
Upgrade
Firefox ESRto a version that resolves this vulnerability.Fixed in 140.11
Event History
May 19, 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 MFSA2026-48?
The severity of MFSA2026-48 is rated as high with a score of 7.
2
How do I fix MFSA2026-48?
To fix MFSA2026-48, update to Firefox ESR version 140.11 or later.
3
What vulnerabilities are addressed in MFSA2026-48?
MFSA2026-48 addresses multiple security vulnerabilities that were found in earlier versions of Firefox ESR.
4
When was MFSA2026-48 published?
MFSA2026-48 was published on May 19, 2026.
5
Which software is affected by MFSA2026-48?
MFSA2026-48 affects Mozilla Firefox ESR.