CVE-2026-12315: Vulnerability in Mozilla Firefox
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
AI Analysis
Technical Summary
CVE-2026-12315 is a mitigation bypass vulnerability affecting the DOM Security component in Mozilla Firefox. It allows bypassing security mitigations designed to protect the DOM, potentially weakening browser security controls. Mozilla fixed this vulnerability in Firefox 152 and Firefox ESR 140.12 as part of a comprehensive security update addressing multiple high and moderate impact vulnerabilities. The vendor advisories confirm the fix and provide detailed references to the underlying bugs.
Potential Impact
The vulnerability could allow an attacker to bypass security mitigations in the DOM Security component, potentially leading to weakened browser security protections. While no specific exploitation in the wild is reported, the impact is considered moderate by Mozilla. This vulnerability is part of a larger set of fixes addressing memory safety bugs, sandbox escapes, privilege escalations, and other security issues in Firefox and Firefox ESR.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 152 and Firefox ESR 140.12. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
CVE-2026-12315: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
CVSS v3.1
Score 9.1critical
Affected software
pkg:github/mozilla/firefox-esrRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12315 is a mitigation bypass vulnerability affecting the DOM Security component in Mozilla Firefox. It allows bypassing security mitigations designed to protect the DOM, potentially weakening browser security controls. Mozilla fixed this vulnerability in Firefox 152 and Firefox ESR 140.12 as part of a comprehensive security update addressing multiple high and moderate impact vulnerabilities. The vendor advisories confirm the fix and provide detailed references to the underlying bugs.
Potential Impact
The vulnerability could allow an attacker to bypass security mitigations in the DOM Security component, potentially leading to weakened browser security protections. While no specific exploitation in the wild is reported, the impact is considered moderate by Mozilla. This vulnerability is part of a larger set of fixes addressing memory safety bugs, sandbox escapes, privilege escalations, and other security issues in Firefox and Firefox ESR.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 152 and Firefox ESR 140.12. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:16.927Z
- 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"}]
Threat ID: 6a314c810b89be6888b4cd6d
Added to database: 6/16/2026, 1:15:45 PM
Last enriched: 6/16/2026, 1:32:41 PM
Last updated: 6/17/2026, 4:19:20 AM
Views: 8
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