CVE-2025-1020: Memory safety bugs fixed in Firefox 135 and Thunderbird 135

Published Feb 4, 2025
·
Updated

Last updated 11 February 2025

Other sources

Memory safety bugs present in Firefox 134 and Thunderbird 134. 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.

Mozilla

Affected Software

5 affected componentsFixes available
debian/firefox
135.0-1
Mozilla Firefox<135.0
Mozilla Thunderbird>=131.0<135.0
Mozilla Firefox<135
135
Mozilla Thunderbird<135
135

Event History

Feb 4, 2025
CVE Published
via Mozilla·12:00 AM
CVE Published
via MITRE·01:58 PM
Data Sourced
via MITRE·01:58 PM
Description
Data Sourced
via NVD·02:15 PM
DescriptionSeverityWeaknessAffected Software
Feb 15, 2025
Data Sourced
via Ubuntu·05:06 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2025-1020?

CVE-2025-1020 is considered a high-severity vulnerability due to the potential for arbitrary code execution.

2

How do I fix CVE-2025-1020?

To fix CVE-2025-1020, upgrade to Firefox or Thunderbird version 135 or later.

3

Which versions of Firefox are affected by CVE-2025-1020?

Firefox versions up to and including 134 are affected by CVE-2025-1020.

4

Which versions of Thunderbird are affected by CVE-2025-1020?

Thunderbird versions up to and including 134 are affected by CVE-2025-1020.

5

What types of vulnerabilities does CVE-2025-1020 include?

CVE-2025-1020 includes memory safety bugs that could potentially lead to memory corruption.

Contact

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