CVE-2026-92021: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition within the Just-In-Time (JIT) compilation component of the JavaScript engine in Mozilla Firefox. Use-after-free bugs occur when a program continues to use memory after it has been freed, which can lead to memory corruption and potentially arbitrary code execution. Mozilla fixed this vulnerability in Firefox ESR 140.16 as part of a security advisory that addressed multiple high-impact vulnerabilities.
Potential Impact
The vulnerability has a high impact rating according to the vendor advisory, indicating that successful exploitation could lead to significant security consequences such as memory corruption or code execution. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox ESR 140.16. Users and administrators should update to this version or later to remediate the issue. No additional mitigation actions are required beyond applying the official update.
CVE-2026-92021: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition within the Just-In-Time (JIT) compilation component of the JavaScript engine in Mozilla Firefox. Use-after-free bugs occur when a program continues to use memory after it has been freed, which can lead to memory corruption and potentially arbitrary code execution. Mozilla fixed this vulnerability in Firefox ESR 140.16 as part of a security advisory that addressed multiple high-impact vulnerabilities.
Potential Impact
The vulnerability has a high impact rating according to the vendor advisory, indicating that successful exploitation could lead to significant security consequences such as memory corruption or code execution. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox ESR 140.16. Users and administrators should update to this version or later to remediate the issue. No additional mitigation actions are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-09-15T12:33:40.656Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-92/","vendor":"Mozilla"}]
Threat ID: 6aa93e6055bf5e2cf5d30fdf
Added to database: 09/15/2026, 12:47:28 UTC
Last enriched: 09/15/2026, 13:32:23 UTC
Last updated: 09/15/2026, 22:11:30 UTC
Views: 3
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