CVE-2026-100762: Vulnerability in Mozilla Firefox
Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
AI Analysis
Technical Summary
CVE-2026-100762 is a use-after-free vulnerability in the DOM Content Processes component of Mozilla Firefox that enables sandbox escape. This flaw was reported by Yaqoub Aldurayhim and has been assigned a high impact rating by Mozilla. The vulnerability was addressed and fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory lists this vulnerability among multiple high-impact memory safety issues resolved in the same update cycle.
Potential Impact
The vulnerability allows an attacker to escape the sandbox environment of Firefox, potentially leading to execution of arbitrary code outside the browser's restricted context. This could compromise the security boundaries intended to isolate web content from the underlying system. The impact is rated high by Mozilla.
Mitigation Recommendations
A fix is available and has been released in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-100762: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to use-after-free in the DOM: Content Processes component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
CVSS v3.1
Score 9.6critical
Affected software
Mozilla
Firefox
pkg:github/mozilla/firefoxRun 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-2026-100762 is a use-after-free vulnerability in the DOM Content Processes component of Mozilla Firefox that enables sandbox escape. This flaw was reported by Yaqoub Aldurayhim and has been assigned a high impact rating by Mozilla. The vulnerability was addressed and fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory lists this vulnerability among multiple high-impact memory safety issues resolved in the same update cycle.
Potential Impact
The vulnerability allows an attacker to escape the sandbox environment of Firefox, potentially leading to execution of arbitrary code outside the browser's restricted context. This could compromise the security boundaries intended to isolate web content from the underlying system. The impact is rated high by Mozilla.
Mitigation Recommendations
A fix is available and has been released in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:15:19.245Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-98/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]
Threat ID: 6abbb3ebf7a7c54106640940
Added to database: 09/29/2026, 12:49:47 UTC
Last enriched: 09/29/2026, 13:33:50 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 50
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