CVE-2026-12311: Vulnerability in Mozilla Firefox
CVE-2026-12311 is a vulnerability in Mozilla Firefox's Security: Process Sandboxing component that allows information disclosure and sandbox escape. This issue was addressed and fixed in Firefox 152 and Firefox ESR 140.12. The vulnerability is part of a broader set of security fixes released by Mozilla in these versions. No known exploits in the wild have been reported. The impact is considered moderate based on the vendor advisory. Users are advised to update to the fixed versions to mitigate this vulnerability.
AI Analysis
Technical Summary
CVE-2026-12311 is an information disclosure and sandbox escape vulnerability in the Security: Process Sandboxing component of Mozilla Firefox. It was fixed in Firefox 152 and Firefox ESR 140.12 as part of Mozilla's June 16, 2026 security advisories (MFSA 2026-57 and MFSA 2026-58). The vulnerability allows an attacker to escape the sandbox environment and potentially access sensitive information. The vendor advisory classifies the impact as moderate and no known exploits have been reported. This fix is included in the official Mozilla releases Firefox 152 and Firefox ESR 140.12.
Potential Impact
The vulnerability allows information disclosure and sandbox escape within Firefox's process sandboxing security mechanism. This could enable an attacker to bypass sandbox restrictions and access sensitive data or perform unauthorized actions within the browser context. However, no active exploitation in the wild has been reported. The impact is rated moderate by Mozilla.
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. Since this is not a cloud service, manual update is required. Patch status is confirmed by the vendor advisories at https://www.mozilla.org/security/advisories/mfsa2026-57/ and https://www.mozilla.org/security/advisories/mfsa2026-58/. No additional mitigation steps are indicated by the vendor.
CVE-2026-12311: Vulnerability in Mozilla Firefox
Description
CVE-2026-12311 is a vulnerability in Mozilla Firefox's Security: Process Sandboxing component that allows information disclosure and sandbox escape. This issue was addressed and fixed in Firefox 152 and Firefox ESR 140.12. The vulnerability is part of a broader set of security fixes released by Mozilla in these versions. No known exploits in the wild have been reported. The impact is considered moderate based on the vendor advisory. Users are advised to update to the fixed versions to mitigate this vulnerability.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12311 is an information disclosure and sandbox escape vulnerability in the Security: Process Sandboxing component of Mozilla Firefox. It was fixed in Firefox 152 and Firefox ESR 140.12 as part of Mozilla's June 16, 2026 security advisories (MFSA 2026-57 and MFSA 2026-58). The vulnerability allows an attacker to escape the sandbox environment and potentially access sensitive information. The vendor advisory classifies the impact as moderate and no known exploits have been reported. This fix is included in the official Mozilla releases Firefox 152 and Firefox ESR 140.12.
Potential Impact
The vulnerability allows information disclosure and sandbox escape within Firefox's process sandboxing security mechanism. This could enable an attacker to bypass sandbox restrictions and access sensitive data or perform unauthorized actions within the browser context. However, no active exploitation in the wild has been reported. The impact is rated moderate by Mozilla.
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. Since this is not a cloud service, manual update is required. Patch status is confirmed by the vendor advisories at https://www.mozilla.org/security/advisories/mfsa2026-57/ and https://www.mozilla.org/security/advisories/mfsa2026-58/. No additional mitigation steps are indicated by the vendor.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:15.120Z
- 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: 6a314c810b89be6888b4cd57
Added to database: 6/16/2026, 1:15:45 PM
Last enriched: 6/16/2026, 1:45:26 PM
Last updated: 6/17/2026, 4:32:26 AM
Views: 7
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