Description
Memory safety bugs present in Firefox ESR 140.5, Thunderbird ESR 140.5, Firefox 145 and Thunderbird 145. 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 146, Firefox ESR 140.6, Thunderbird 146, and Thunderbird 140.6.
Affected products
mozilla: firefox; mozilla: thunderbird
References5
- www.mozilla.org/security/advisories/mfsa2025-92/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-94/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-95/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-96/ Vendor Advisory
- bugzilla.mozilla.org/buglist.cgi?bug_id=1966501%2C1997639 Broken LinkIssue Tracking
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 41 · as of 11 November 2026
- CWE
- CWE-787CWE-119
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