CVE-2025-9187: Memory safety bugs fixed in Firefox 142 and Thunderbird 142
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
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 142 - Upgrade
Upgrade
Mozilla Firefoxto a version that resolves this vulnerability.Fixed in 142 - Upgrade
Upgrade
Mozilla Thunderbirdto a version that resolves this vulnerability.Fixed in 142
Event History
Peer vulnerabilities
Found alongside the following vulnerabilities.
Frequently Asked Questions
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.
How do I fix CVE-2025-9187?
To fix CVE-2025-9187, users should upgrade to Firefox and Thunderbird versions 142 or later.
Which versions of Firefox are affected by CVE-2025-9187?
CVE-2025-9187 affects all versions of Firefox prior to version 142.
Which versions of Thunderbird are affected by CVE-2025-9187?
CVE-2025-9187 affects all versions of Thunderbird prior to version 142.
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.