MFSA2026-04: Security Vulnerabilities fixed in Thunderbird 147
Published Jan 13, 2026
·Updated
Security Vulnerabilities fixed in Thunderbird 147
Affected Software
1 affected componentFixes available
Mozilla Thunderbird<147
147
Event History
Jan 13, 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 MFSA2026-04?
The severity of MFSA2026-04 is rated as critical due to the potential for remote code execution.
2
How do I fix MFSA2026-04?
To fix MFSA2026-04, upgrade to Mozilla Thunderbird version 147 or later.
3
What types of vulnerabilities are addressed in MFSA2026-04?
MFSA2026-04 addresses several security vulnerabilities related to remote code execution and denial of service.
4
Which versions of Thunderbird are affected by MFSA2026-04?
MFSA2026-04 affects all versions of Thunderbird prior to 147.
5
Is there a risk of data loss with MFSA2026-04?
Yes, exploitation of the vulnerabilities in MFSA2026-04 could lead to potential data loss.