CVE-2026-100829: Vulnerability in Mozilla Firefox
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.
AI Analysis
Technical Summary
CVE-2026-100829 is a security vulnerability in Mozilla Firefox's DOM security component that allows bypassing of mitigation controls. The flaw was fixed in Firefox ESR 153.4 and Firefox 157. This vulnerability is one among many high-impact bugs addressed in the Mozilla security advisory MFSA 2026-100. The advisory confirms the fix and categorizes the impact as high.
Potential Impact
The vulnerability allows bypassing mitigation mechanisms in the DOM security component, which could potentially lead to security issues if exploited. However, there are no known active exploits in the wild. The impact is rated as high by Mozilla, indicating a serious security concern if left unpatched.
Mitigation Recommendations
Users and administrators should update Firefox to ESR 153.4 or later, or Firefox 157 or later, where this vulnerability is fixed. Applying these official updates fully mitigates the risk from this vulnerability.
CVE-2026-100829: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox ESR 153.4 and Firefox 157.
Affected software
Mozilla
Firefox
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-100829 is a security vulnerability in Mozilla Firefox's DOM security component that allows bypassing of mitigation controls. The flaw was fixed in Firefox ESR 153.4 and Firefox 157. This vulnerability is one among many high-impact bugs addressed in the Mozilla security advisory MFSA 2026-100. The advisory confirms the fix and categorizes the impact as high.
Potential Impact
The vulnerability allows bypassing mitigation mechanisms in the DOM security component, which could potentially lead to security issues if exploited. However, there are no known active exploits in the wild. The impact is rated as high by Mozilla, indicating a serious security concern if left unpatched.
Mitigation Recommendations
Users and administrators should update Firefox to ESR 153.4 or later, or Firefox 157 or later, where this vulnerability is fixed. Applying these official updates fully mitigates the risk from this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:18:58.255Z
- 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"}]
Threat ID: 6abbb3f9f7a7c541066409cc
Added to database: 09/29/2026, 12:50:01 UTC
Last enriched: 09/29/2026, 13:02:56 UTC
Last updated: 09/29/2026, 18:20:13 UTC
Views: 9
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