Use-after-free in the JavaScript Engine: JIT component. (CVE-2026-92021)
CVE-2026-92021 is a use-after-free vulnerability in the JavaScript Engine's Just-In-Time (JIT) compilation component of Firefox ESR. This vulnerability has been assigned a high impact rating by Mozilla. It was fixed in Firefox ESR version 140.16. The issue could potentially allow for memory safety violations, but no known exploits in the wild have been reported. The vendor advisory confirms the availability of an official fix.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the JIT component of Firefox ESR's JavaScript Engine. Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, potentially leading to crashes or arbitrary code execution. Mozilla assigned a high impact to this issue and addressed it in Firefox ESR 140.16. The advisory is part of a broader set of memory safety fixes released simultaneously. No specific exploitation details are provided.
Potential Impact
The vulnerability is rated high impact by Mozilla, indicating that successful exploitation could lead to significant security consequences such as memory corruption or code execution. However, there are no reports of active exploitation in the wild. The fix in Firefox ESR 140.16 mitigates the risk.
Mitigation Recommendations
Users and administrators should update Firefox ESR to version 140.16 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in this version. No additional mitigation steps are required once the update is applied.
Use-after-free in the JavaScript Engine: JIT component. (CVE-2026-92021)
Description
CVE-2026-92021 is a use-after-free vulnerability in the JavaScript Engine's Just-In-Time (JIT) compilation component of Firefox ESR. This vulnerability has been assigned a high impact rating by Mozilla. It was fixed in Firefox ESR version 140.16. The issue could potentially allow for memory safety violations, but no known exploits in the wild have been reported. The vendor advisory confirms the availability of an official fix.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the JIT component of Firefox ESR's JavaScript Engine. Use-after-free vulnerabilities occur when a program continues to use memory after it has been freed, potentially leading to crashes or arbitrary code execution. Mozilla assigned a high impact to this issue and addressed it in Firefox ESR 140.16. The advisory is part of a broader set of memory safety fixes released simultaneously. No specific exploitation details are provided.
Potential Impact
The vulnerability is rated high impact by Mozilla, indicating that successful exploitation could lead to significant security consequences such as memory corruption or code execution. However, there are no reports of active exploitation in the wild. The fix in Firefox ESR 140.16 mitigates the risk.
Mitigation Recommendations
Users and administrators should update Firefox ESR to version 140.16 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in this version. No additional mitigation steps are required once the update is applied.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-8gpq-5x64-h429
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-92021"]
- State
- PUBLISHED
Threat ID: 6aaa081255bf5e2cf5ea4a6c
Added to database: 09/16/2026, 03:08:02 UTC
Last enriched: 09/16/2026, 05:07:28 UTC
Last updated: 09/16/2026, 05:07:28 UTC
Views: 3
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