CVE-2026-100770: 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
This vulnerability (CVE-2026-100770) is a sandbox escape due to a use-after-free condition in the DOM: Content Processes component of Mozilla Firefox. The flaw could allow malicious content running in a content process to escape the sandbox protections, potentially leading to higher privilege code execution or other impacts. Mozilla addressed this issue with patches released in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The advisory categorizes the impact as high and references Bug 2068322 for technical details.
Potential Impact
The vulnerability enables sandbox escape, which can undermine the security boundary between web content and the underlying system. This could allow attackers to execute code with elevated privileges or access restricted resources beyond the browser sandbox. The impact is rated high by Mozilla.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. No additional mitigations are indicated by the vendor advisory.
CVE-2026-100770: 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
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-100770) is a sandbox escape due to a use-after-free condition in the DOM: Content Processes component of Mozilla Firefox. The flaw could allow malicious content running in a content process to escape the sandbox protections, potentially leading to higher privilege code execution or other impacts. Mozilla addressed this issue with patches released in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. The advisory categorizes the impact as high and references Bug 2068322 for technical details.
Potential Impact
The vulnerability enables sandbox escape, which can undermine the security boundary between web content and the underlying system. This could allow attackers to execute code with elevated privileges or access restricted resources beyond the browser sandbox. The impact is rated high by Mozilla.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox ESR 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. No additional mitigations are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:15:26.594Z
- 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: 6abbb3edf7a7c5410664096e
Added to database: 09/29/2026, 12:49:49 UTC
Last enriched: 09/29/2026, 13:33:21 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 2
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