CVE-2026-100758: Vulnerability in Mozilla Firefox
Sandbox escape in the DOM: Navigation 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-2026-100758 is a sandbox escape vulnerability affecting the DOM Navigation component in Mozilla Firefox. The flaw could allow an attacker to break out of the browser's sandbox, which is designed to isolate web content and limit its access to the system. Mozilla addressed this issue by releasing patches in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory categorizes the impact as high and provides references to the underlying bug report (Bug 2049792).
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox protections in Firefox, potentially enabling them to execute code with higher privileges or access sensitive system resources. The vendor rates the impact as high, indicating significant security implications if exploited.
Mitigation Recommendations
This vulnerability has been fixed 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 mitigate the risk. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-100758: Vulnerability in Mozilla Firefox
Description
Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100758 is a sandbox escape vulnerability affecting the DOM Navigation component in Mozilla Firefox. The flaw could allow an attacker to break out of the browser's sandbox, which is designed to isolate web content and limit its access to the system. Mozilla addressed this issue by releasing patches in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory categorizes the impact as high and provides references to the underlying bug report (Bug 2049792).
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the sandbox protections in Firefox, potentially enabling them to execute code with higher privileges or access sensitive system resources. The vendor rates the impact as high, indicating significant security implications if exploited.
Mitigation Recommendations
This vulnerability has been fixed 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 mitigate the risk. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:15:15.623Z
- 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: 6abbb3ebf7a7c5410664093c
Added to database: 09/29/2026, 12:49:47 UTC
Last enriched: 09/29/2026, 13:34:03 UTC
Last updated: 09/29/2026, 18:20:13 UTC
Views: 2
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