CVE-2026-100781: Vulnerability in Mozilla Firefox
Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender 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 involves incorrect boundary conditions in the Graphics: WebRender component of Mozilla Firefox, leading to a sandbox escape. The flaw was identified and fixed by Mozilla in multiple Firefox ESR and standard releases. The vendor advisory confirms the fix availability and classifies the impact as high.
Potential Impact
Successful exploitation could allow an attacker to escape the sandbox protections of Firefox, potentially leading to execution of code outside the browser's restricted environment. This elevates the risk of further compromise on the host system.
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. Applying these official updates fully mitigates the risk.
CVE-2026-100781: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to incorrect boundary conditions in the Graphics: WebRender 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
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves incorrect boundary conditions in the Graphics: WebRender component of Mozilla Firefox, leading to a sandbox escape. The flaw was identified and fixed by Mozilla in multiple Firefox ESR and standard releases. The vendor advisory confirms the fix availability and classifies the impact as high.
Potential Impact
Successful exploitation could allow an attacker to escape the sandbox protections of Firefox, potentially leading to execution of code outside the browser's restricted environment. This elevates the risk of further compromise on the host system.
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. Applying these official updates fully mitigates the risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:16:55.886Z
- 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: 6abbb3eff7a7c5410664097e
Added to database: 09/29/2026, 12:49:51 UTC
Last enriched: 09/29/2026, 13:32:42 UTC
Last updated: 09/29/2026, 18:20:13 UTC
Views: 2
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