CVE-2025-9187: Memory safety bugs fixed in Firefox 142 and Thunderbird 142
Published Aug 19, 2025
·Updated
Memory safety bugs present in Firefox 141 and Thunderbird 141. 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
6 affected componentsFixes available
Mozilla Firefox<142
Mozilla Thunderbird<142
Mozilla Firefox<142.0
Mozilla Thunderbird<142.0
Mozilla Thunderbird<142
142
Mozilla Firefox<142
142
Event History
Aug 19, 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·08:33 PM
Data Sourced
via MITRE·08:33 PM
Description
Data Sourced
via NVD·09:15 PM
DescriptionSeverityWeaknessAffected Software
Feb 28, 57989
Event
via FIRST·07:47 AM
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
1
What is the severity of CVE-2025-9187?
CVE-2025-9187 has been categorized as a critical vulnerability due to its potential for memory corruption and arbitrary code execution.
2
How do I fix CVE-2025-9187?
To fix CVE-2025-9187, users should upgrade to Firefox and Thunderbird versions 142 or later.
3
Which versions of Firefox are affected by CVE-2025-9187?
CVE-2025-9187 affects all versions of Firefox prior to version 142.
4
Which versions of Thunderbird are affected by CVE-2025-9187?
CVE-2025-9187 affects all versions of Thunderbird prior to version 142.
5
What types of issues does CVE-2025-9187 involve?
CVE-2025-9187 involves memory safety bugs that can lead to memory corruption in Firefox and Thunderbird.