Vulnerability Description
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. This vulnerability was fixed in Firefox 142 and Thunderbird 142.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 142.0 |
| Mozilla | Thunderbird | < 142.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/buglist.cgi?bug_id=1825621%2C1970079%2C1976736%2C19Broken Link
- https://www.mozilla.org/security/advisories/mfsa2025-64/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-70/Vendor Advisory
FAQ
What is CVE-2025-9187?
CVE-2025-9187 is a vulnerability with a CVSS score of 9.8 (CRITICAL). 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...
How severe is CVE-2025-9187?
CVE-2025-9187 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2025-9187?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox, Mozilla Thunderbird.