CVE-2026-100786: Vulnerability in Mozilla Firefox
Sandbox escape due to use-after-free in the Graphics 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
This vulnerability is a use-after-free in the Graphics component of Mozilla Firefox that enables sandbox escape. It was addressed by Mozilla in multiple Firefox ESR and standard releases, specifically fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory confirms the fix and categorizes the impact as high.
Potential Impact
Successful exploitation could allow an attacker to escape the sandbox protection in Firefox, potentially leading to execution of arbitrary code outside the browser's restricted environment. This elevates the risk of further system compromise.
Mitigation Recommendations
Users should update to Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, Firefox ESR 140.17, or later versions where this vulnerability is fixed. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-100786: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to use-after-free in the Graphics 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
This vulnerability is a use-after-free in the Graphics component of Mozilla Firefox that enables sandbox escape. It was addressed by Mozilla in multiple Firefox ESR and standard releases, specifically fixed in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The vendor advisory confirms the fix and categorizes the impact as high.
Potential Impact
Successful exploitation could allow an attacker to escape the sandbox protection in Firefox, potentially leading to execution of arbitrary code outside the browser's restricted environment. This elevates the risk of further system compromise.
Mitigation Recommendations
Users should update to Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, Firefox ESR 140.17, or later versions where this vulnerability is fixed. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:17:08.056Z
- 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: 6abbb3f1f7a7c5410664098a
Added to database: 09/29/2026, 12:49:53 UTC
Last enriched: 09/29/2026, 13:18:50 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 3
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