CVE-2026-12312: Vulnerability in Mozilla Firefox
Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
AI Analysis
Technical Summary
CVE-2026-12312 is a memory safety bug in Mozilla Firefox identified and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple memory safety vulnerabilities addressed in these versions, some with evidence of memory corruption that could have allowed arbitrary code execution with sufficient effort. The vendor advisories (MFSA 2026-57 and MFSA 2026-58) provide detailed information on these fixes and confirm the remediation. The vulnerability affects Firefox versions before 152 and Firefox ESR versions before 140.12.
Potential Impact
The vulnerability involves memory safety issues that could lead to memory corruption. While no active exploitation has been reported, such bugs have the potential to be exploited for arbitrary code execution. The impact is assessed as moderate based on the vendor advisory, reflecting the potential severity if exploited but no confirmed active attacks.
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 this issue. No additional mitigation actions are required beyond applying these updates.
CVE-2026-12312: Vulnerability in Mozilla Firefox
Description
Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
CVSS v3.1
Score 7.5high
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-2026-12312 is a memory safety bug in Mozilla Firefox identified and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple memory safety vulnerabilities addressed in these versions, some with evidence of memory corruption that could have allowed arbitrary code execution with sufficient effort. The vendor advisories (MFSA 2026-57 and MFSA 2026-58) provide detailed information on these fixes and confirm the remediation. The vulnerability affects Firefox versions before 152 and Firefox ESR versions before 140.12.
Potential Impact
The vulnerability involves memory safety issues that could lead to memory corruption. While no active exploitation has been reported, such bugs have the potential to be exploited for arbitrary code execution. The impact is assessed as moderate based on the vendor advisory, reflecting the potential severity if exploited but no confirmed active attacks.
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 this issue. No additional mitigation actions are required beyond applying these updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:15.534Z
- 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: 6a314c810b89be6888b4cd5d
Added to database: 6/16/2026, 1:15:45 PM
Last enriched: 6/16/2026, 1:45:18 PM
Last updated: 6/17/2026, 5:00:01 AM
Views: 10
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