CVE-2026-12305: 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-2026-12305 is a memory safety bug in Mozilla Firefox reported by Zijie Zhao and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple memory safety vulnerabilities addressed in these versions, some of which showed evidence of memory corruption that could lead to arbitrary code execution if exploited. The Mozilla advisories MFSA2026-57 and MFSA2026-58 detail these fixes and confirm the remediation in the specified versions. No CVSS score is provided, but the impact is assessed as moderate within the context of multiple related vulnerabilities.
Potential Impact
The vulnerability involves memory safety issues that could lead to memory corruption. While no active exploitation in the wild is reported, the potential impact includes arbitrary code execution if an attacker successfully exploits the bug. This can compromise the security and integrity of the affected Firefox installations prior to version 152 and ESR 140.12.
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-2026-12305: 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-2026-12305 is a memory safety bug in Mozilla Firefox reported by Zijie Zhao and fixed in Firefox 152 and Firefox ESR 140.12. It is one of multiple memory safety vulnerabilities addressed in these versions, some of which showed evidence of memory corruption that could lead to arbitrary code execution if exploited. The Mozilla advisories MFSA2026-57 and MFSA2026-58 detail these fixes and confirm the remediation in the specified versions. No CVSS score is provided, but the impact is assessed as moderate within the context of multiple related vulnerabilities.
Potential Impact
The vulnerability involves memory safety issues that could lead to memory corruption. While no active exploitation in the wild is reported, the potential impact includes arbitrary code execution if an attacker successfully exploits the bug. This can compromise the security and integrity of the affected Firefox installations prior to version 152 and ESR 140.12.
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
- 2026-06-15T15:08:12.602Z
- 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: 6a314c7e0b89be6888b4cc94
Added to database: 6/16/2026, 1:15:42 PM
Last enriched: 6/16/2026, 1:45:59 PM
Last updated: 6/17/2026, 5:08:32 AM
Views: 8
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