Vulnerability record · CVE-2026-12328 · published 16 June 2026
CVE-2026-12328: Mozilla firefox classic buffer overflow vulnerability
Mozilla · Firefox
Memory safety bugs present in Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. 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 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
Description
Memory safety bugs present in Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird ESR 140.11, Firefox 151 and Thunderbird 151. 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 152, Firefox ESR 140.12, Firefox ESR 115.37, Thunderbird 152, and Thunderbird 140.12.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-12328), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.