CVE-2026-12328: Vulnerability in 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.
AI Analysis
Technical Summary
CVE-2026-12328 encompasses memory safety bugs affecting specific versions of Mozilla Firefox and Thunderbird, including Firefox ESR 115.36, ESR 140.11, Thunderbird ESR 140.11, Firefox 151, and Thunderbird 151. These bugs involve memory corruption issues that could be exploited to run arbitrary code. Mozilla addressed these vulnerabilities in Firefox 152, Firefox ESR 115.37, ESR 140.12, Thunderbird 152, and Thunderbird ESR 140.12. The vulnerabilities are part of a broader set of memory safety issues fixed in these releases, with a CVSS v3.1 base score of 8.1, indicating high impact on confidentiality, integrity, and availability. The vendor advisories provide detailed references and confirm the fixes.
Potential Impact
The vulnerabilities allow for potential arbitrary code execution due to memory corruption in affected Firefox and Thunderbird versions. This impacts confidentiality, integrity, and availability of the affected software. No known exploits in the wild have been reported at the time of publication. The high CVSS score reflects the critical nature of these memory safety bugs.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 152, Firefox ESR 115.37, Firefox ESR 140.12, Thunderbird 152, and Thunderbird ESR 140.12. Users and administrators should upgrade to these fixed versions to remediate the vulnerabilities. Patch status is confirmed by the vendor advisories. No additional mitigation beyond applying these updates is indicated.
CVE-2026-12328: Vulnerability in Mozilla Firefox
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 v3.1
Score 8.1high
Affected software
pkg:github/mozilla/firefoxpkg:github/mozilla/thunderbirdRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12328 encompasses memory safety bugs affecting specific versions of Mozilla Firefox and Thunderbird, including Firefox ESR 115.36, ESR 140.11, Thunderbird ESR 140.11, Firefox 151, and Thunderbird 151. These bugs involve memory corruption issues that could be exploited to run arbitrary code. Mozilla addressed these vulnerabilities in Firefox 152, Firefox ESR 115.37, ESR 140.12, Thunderbird 152, and Thunderbird ESR 140.12. The vulnerabilities are part of a broader set of memory safety issues fixed in these releases, with a CVSS v3.1 base score of 8.1, indicating high impact on confidentiality, integrity, and availability. The vendor advisories provide detailed references and confirm the fixes.
Potential Impact
The vulnerabilities allow for potential arbitrary code execution due to memory corruption in affected Firefox and Thunderbird versions. This impacts confidentiality, integrity, and availability of the affected software. No known exploits in the wild have been reported at the time of publication. The high CVSS score reflects the critical nature of these memory safety bugs.
Mitigation Recommendations
Mozilla has released official fixes for these vulnerabilities in Firefox 152, Firefox ESR 115.37, Firefox ESR 140.12, Thunderbird 152, and Thunderbird ESR 140.12. Users and administrators should upgrade to these fixed versions to remediate the vulnerabilities. Patch status is confirmed by the vendor advisories. No additional mitigation beyond applying these updates is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:22.260Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-57/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-58/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-59/","vendor":"Mozilla"}]
Threat ID: 6a314c830b89be6888b4cdec
Added to database: 06/16/2026, 13:15:47 UTC
Last enriched: 07/15/2026, 13:34:26 UTC
Last updated: 07/31/2026, 19:22:57 UTC
Views: 121
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