REDHAT-BUG-2420502: Medium severity Mozilla Firefox vulnerability

Published Dec 9, 2025
·
Updated

Memory safety bugs present in Firefox ESR 140.5, Thunderbird ESR 140.5, Firefox 145 and Thunderbird 145. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 146 and Firefox ESR < 140.6.

Affected Software

4 affected components
Mozilla Firefox<146
Mozilla Firefox ESR<140.6
Mozilla Thunderbird<146
Mozilla Thunderbird ESR<140.6

Event History

Dec 9, 2025
Data Sourced
via Red Hat·02:01 PM
DescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of REDHAT-BUG-2420502?

The severity of REDHAT-BUG-2420502 is critical due to potential memory corruption leading to arbitrary code execution.

2

How do I fix REDHAT-BUG-2420502?

To fix REDHAT-BUG-2420502, update Firefox and Thunderbird to their latest versions beyond the affected versions.

3

Which versions are affected by REDHAT-BUG-2420502?

REDHAT-BUG-2420502 affects Firefox versions up to 146, Firefox ESR up to 140.6, Thunderbird versions up to 146, and Thunderbird ESR up to 140.6.

4

What types of software are impacted by REDHAT-BUG-2420502?

REDHAT-BUG-2420502 impacts Mozilla Firefox, Firefox ESR, Mozilla Thunderbird, and Thunderbird ESR.

5

What are the consequences of not addressing REDHAT-BUG-2420502?

Failure to address REDHAT-BUG-2420502 could lead to exploitation resulting in arbitrary code execution on affected systems.

Contact

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