CVE-2026-84142
Critical
9.8 CVSS v3.1
- Published
- Sep 1, 2026
- Updated
- Sep 3, 2026
- Vendor
- Mozilla
- Affected versions
- See affected products
- Weakness
- CWE-119, CWE-200
Summary
Internally found bugs present in Thunderbird 154. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155 and Thunderbird 155.
Severity
Critical (9.8)CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
- Mozilla Firefox < 155.0.0
- Mozilla Thunderbird < 155.0
Exploitation status
Unknown
Technical details
Technical analysis has not been written for this record yet.
Mitigation & remediation
Follow the vendor advisory linked below for patches and workarounds.