CVE-2025-9187 — Memory safety bugs present in Firefox 141 and Thunderbird 141.

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.

References

• https://bugzilla.mozilla.org/buglist.cgi?bug_id=1825621%2C1970079%2C1976736%2C1979072
• https://www.mozilla.org/security/advisories/mfsa2025-64/
• https://www.mozilla.org/security/advisories/mfsa2025-70/