CVE-2025-5268: Memory safety bugs fixed in Firefox 139, Thunderbird 139, Firefox ESR 128.11, and Thunderbird 128.11

Published May 27, 2025
·
Updated

Memory safety bugs present in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10. 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.

Affected Software

12 affected componentsFixes available
Mozilla Firefox<139
Mozilla Thunderbird<139
Mozilla Firefox ESR<128.11
Mozilla Thunderbird<128.11
Mozilla Thunderbird<128.11
128.11
Mozilla Thunderbird<139
139
Mozilla Firefox ESR<128.11
128.11
Mozilla Firefox<139
139
Mozilla Firefox<128.11.0
Mozilla Firefox<139.0
Mozilla Thunderbird<128.11.0
Mozilla Thunderbird>=129.0<139.0

Event History

May 27, 2025
CVE Published
via Mozilla·12:00 AM
Data Sourced
via Mozilla·12:00 AM
DescriptionSeverityAffected Software
Updated
via Mozilla·12:00 AM
Affected Software
CVE Published
via MITRE·12:29 PM
Data Sourced
via MITRE·12:29 PM
Description
Data Sourced
via Red Hat·01:01 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·01:15 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2025-5268?

CVE-2025-5268 is considered a high severity vulnerability due to the potential for memory corruption that could allow arbitrary code execution.

2

How do I fix CVE-2025-5268?

To fix CVE-2025-5268, update your Mozilla Firefox or Thunderbird to version 139 or Mozilla Firefox ESR to version 128.11.

3

What versions are affected by CVE-2025-5268?

CVE-2025-5268 affects Mozilla Firefox versions up to 138, Thunderbird versions up to 138, and Firefox ESR versions up to 128.10.

4

What types of software are impacted by CVE-2025-5268?

CVE-2025-5268 impacts Mozilla Firefox, Mozilla Thunderbird, and Mozilla Firefox ESR.

5

Are there any known exploits for CVE-2025-5268?

While there is no confirmation of active exploits, the nature of CVE-2025-5268 indicates that it could potentially be exploited with sufficient technical effort.

Contact

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