CVE-2026-12296: Vulnerability in Mozilla Firefox
CVE-2026-12296 is a sandbox escape vulnerability in the Security: Process Sandboxing component of Mozilla Firefox. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12. It is classified with high impact by Mozilla. The flaw could allow an attacker to escape the sandbox protections designed to isolate processes. Multiple related sandbox escape and memory safety vulnerabilities were addressed in these Firefox releases.
AI Analysis
Technical Summary
CVE-2026-12296 is a high-impact sandbox escape vulnerability affecting the Security: Process Sandboxing component in Mozilla Firefox. The vulnerability allows an attacker to bypass sandbox restrictions, potentially leading to privilege escalation or code execution outside the sandbox. Mozilla fixed this issue in Firefox 152 and Firefox ESR 140.12. The vendor advisories (MFSA 2026-57 and MFSA 2026-58) confirm the fix and classify the impact as high. This vulnerability is part of a broader set of security fixes in these releases addressing sandbox escapes, memory safety bugs, use-after-free, and other security issues.
Potential Impact
The vulnerability enables sandbox escape, which undermines the security boundary that isolates Firefox processes. This could allow an attacker to execute code with higher privileges or access sensitive information outside the sandbox. The impact is rated high by Mozilla, indicating serious security implications if exploited.
Mitigation Recommendations
This vulnerability is fixed 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 steps are required beyond applying the official updates.
CVE-2026-12296: Vulnerability in Mozilla Firefox
Description
CVE-2026-12296 is a sandbox escape vulnerability in the Security: Process Sandboxing component of Mozilla Firefox. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12. It is classified with high impact by Mozilla. The flaw could allow an attacker to escape the sandbox protections designed to isolate processes. Multiple related sandbox escape and memory safety vulnerabilities were addressed in these Firefox releases.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12296 is a high-impact sandbox escape vulnerability affecting the Security: Process Sandboxing component in Mozilla Firefox. The vulnerability allows an attacker to bypass sandbox restrictions, potentially leading to privilege escalation or code execution outside the sandbox. Mozilla fixed this issue in Firefox 152 and Firefox ESR 140.12. The vendor advisories (MFSA 2026-57 and MFSA 2026-58) confirm the fix and classify the impact as high. This vulnerability is part of a broader set of security fixes in these releases addressing sandbox escapes, memory safety bugs, use-after-free, and other security issues.
Potential Impact
The vulnerability enables sandbox escape, which undermines the security boundary that isolates Firefox processes. This could allow an attacker to execute code with higher privileges or access sensitive information outside the sandbox. The impact is rated high by Mozilla, indicating serious security implications if exploited.
Mitigation Recommendations
This vulnerability is fixed 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 steps are required beyond applying the official updates.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:08.752Z
- 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: 6a314c7b0b89be6888b4cbd4
Added to database: 6/16/2026, 1:15:39 PM
Last enriched: 6/16/2026, 1:46:45 PM
Last updated: 6/17/2026, 5:03:40 AM
Views: 6
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