CVE-2026-100804: Vulnerability in Mozilla Firefox
Sandbox escape due to use-after-free in the Preferences: Backend component. This vulnerability was fixed in Firefox 157.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the Preferences: Backend component of Mozilla Firefox, which can lead to sandbox escape. The flaw was identified and fixed in Firefox 157. The sandbox escape means that an attacker could potentially bypass the browser's security isolation mechanisms. Mozilla has assigned a moderate impact level to this specific vulnerability. The vendor advisory confirms the fix was implemented in Firefox 157 and provides no indication of active exploitation.
Potential Impact
The vulnerability allows sandbox escape due to a use-after-free bug in the Preferences: Backend component. This could enable an attacker to execute code outside the browser sandbox, increasing the risk of system compromise. However, the impact is rated moderate by Mozilla, and no active exploitation has been reported.
Mitigation Recommendations
Mozilla fixed this vulnerability in Firefox 157. Users and administrators should update to Firefox 157 or later to remediate this issue. Since the vulnerability is patched, no additional mitigation steps are required.
CVE-2026-100804: Vulnerability in Mozilla Firefox
Description
Sandbox escape due to use-after-free in the Preferences: Backend component. This vulnerability was fixed in Firefox 157.
CVSS v3.1
Score 9.6critical
Affected software
Mozilla
Firefox
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the Preferences: Backend component of Mozilla Firefox, which can lead to sandbox escape. The flaw was identified and fixed in Firefox 157. The sandbox escape means that an attacker could potentially bypass the browser's security isolation mechanisms. Mozilla has assigned a moderate impact level to this specific vulnerability. The vendor advisory confirms the fix was implemented in Firefox 157 and provides no indication of active exploitation.
Potential Impact
The vulnerability allows sandbox escape due to a use-after-free bug in the Preferences: Backend component. This could enable an attacker to execute code outside the browser sandbox, increasing the risk of system compromise. However, the impact is rated moderate by Mozilla, and no active exploitation has been reported.
Mitigation Recommendations
Mozilla fixed this vulnerability in Firefox 157. Users and administrators should update to Firefox 157 or later to remediate this issue. Since the vulnerability is patched, no additional mitigation steps are required.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-26T19:17:53.460Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"}]
Threat ID: 6abbb3f3f7a7c541066409a4
Added to database: 09/29/2026, 12:49:55 UTC
Last enriched: 09/29/2026, 13:17:49 UTC
Last updated: 09/29/2026, 15:30:19 UTC
Views: 4
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