Description
Memory safety bugs present in Firefox 137 and Thunderbird 137. 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 138 and Thunderbird 138.
Affected products
mozilla: firefox; mozilla: thunderbird
References3
- www.mozilla.org/security/advisories/mfsa2025-28/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-31/ Vendor Advisory
- bugzilla.mozilla.org/buglist.cgi?bug_id=1924108%2C1950780%2C195… Broken Link
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 24 · as of 7 November 2026
- CWE
- CWE-119
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