CVE-2026-12294: Vulnerability in Mozilla Firefox
CVE-2026-12294 is a high-impact sandbox escape vulnerability in the DOM Workers component of Mozilla Firefox. This vulnerability allows an attacker to escape the browser's sandbox environment, potentially leading to privilege escalation or arbitrary code execution. The issue was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Multiple related security vulnerabilities were addressed in these releases, indicating a broad security update. No known exploits in the wild have been reported at this time.
AI Analysis
Technical Summary
CVE-2026-12294 is a sandbox escape vulnerability affecting the DOM Workers component in Mozilla Firefox. It was reported by Quy Pham and classified as high impact. The vulnerability was resolved in Firefox 152 and the corresponding ESR versions 140.12 and 115.37. The fix is part of a larger security update addressing multiple high-impact vulnerabilities including privilege escalations, memory safety bugs, use-after-free, and sandbox escapes across various Firefox components. The vendor advisories confirm the remediation and provide detailed references to the underlying bugs.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox protections of Firefox's DOM Workers component. This could lead to execution of arbitrary code outside the sandbox, increasing the risk of privilege escalation and system compromise. The vulnerability is considered high impact due to the potential severity of sandbox escapes in a web browser environment.
Mitigation Recommendations
This vulnerability has been fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation actions are required beyond applying the official vendor patches.
CVE-2026-12294: Vulnerability in Mozilla Firefox
Description
CVE-2026-12294 is a high-impact sandbox escape vulnerability in the DOM Workers component of Mozilla Firefox. This vulnerability allows an attacker to escape the browser's sandbox environment, potentially leading to privilege escalation or arbitrary code execution. The issue was fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Multiple related security vulnerabilities were addressed in these releases, indicating a broad security update. No known exploits in the wild have been reported at this time.
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12294 is a sandbox escape vulnerability affecting the DOM Workers component in Mozilla Firefox. It was reported by Quy Pham and classified as high impact. The vulnerability was resolved in Firefox 152 and the corresponding ESR versions 140.12 and 115.37. The fix is part of a larger security update addressing multiple high-impact vulnerabilities including privilege escalations, memory safety bugs, use-after-free, and sandbox escapes across various Firefox components. The vendor advisories confirm the remediation and provide detailed references to the underlying bugs.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox protections of Firefox's DOM Workers component. This could lead to execution of arbitrary code outside the sandbox, increasing the risk of privilege escalation and system compromise. The vulnerability is considered high impact due to the potential severity of sandbox escapes in a web browser environment.
Mitigation Recommendations
This vulnerability has been fixed in Firefox 152, Firefox ESR 140.12, and Firefox ESR 115.37. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation actions are required beyond applying the official vendor patches.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:07.929Z
- 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"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-59/","vendor":"Mozilla"}]
Threat ID: 6a314c7b0b89be6888b4cbc8
Added to database: 6/16/2026, 1:15:39 PM
Last enriched: 6/16/2026, 1:46:55 PM
Last updated: 6/17/2026, 4:59:34 AM
Views: 12
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