CVE-2026-12321: Vulnerability in Mozilla Firefox
CVE-2026-12321 is a vulnerability in Mozilla Firefox involving JIT miscompilation in the JavaScript WebAssembly component. This issue was addressed and fixed in Firefox version 152. The vulnerability is classified with low impact in the advisory but is part of a broader set of security fixes released in Firefox 152. No known exploits in the wild have been reported for this specific issue.
AI Analysis
Technical Summary
The vulnerability CVE-2026-12321 concerns a Just-In-Time (JIT) miscompilation flaw in the JavaScript WebAssembly component of Mozilla Firefox. This flaw could potentially cause incorrect code generation during JIT compilation, which may lead to unexpected behavior or security issues. Mozilla fixed this vulnerability in Firefox 152 as part of a security update that addressed multiple high, moderate, and low impact vulnerabilities. The vendor advisory confirms the fix and categorizes the impact of this specific vulnerability as low.
Potential Impact
The impact of this vulnerability is considered low according to the Mozilla advisory. While JIT miscompilation can sometimes lead to security issues such as code execution or memory corruption, no evidence or known exploits have been reported for this vulnerability. It is part of a larger security update that addresses multiple vulnerabilities with varying impacts, but this particular issue is assessed as low impact.
Mitigation Recommendations
A fix for this vulnerability is available in Mozilla Firefox version 152. Users and administrators should update to Firefox 152 or later to remediate this issue. Since the vulnerability is fixed in this official release, no additional mitigation steps are necessary beyond applying the update.
CVE-2026-12321: Vulnerability in Mozilla Firefox
Description
CVE-2026-12321 is a vulnerability in Mozilla Firefox involving JIT miscompilation in the JavaScript WebAssembly component. This issue was addressed and fixed in Firefox version 152. The vulnerability is classified with low impact in the advisory but is part of a broader set of security fixes released in Firefox 152. No known exploits in the wild have been reported for this specific issue.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-12321 concerns a Just-In-Time (JIT) miscompilation flaw in the JavaScript WebAssembly component of Mozilla Firefox. This flaw could potentially cause incorrect code generation during JIT compilation, which may lead to unexpected behavior or security issues. Mozilla fixed this vulnerability in Firefox 152 as part of a security update that addressed multiple high, moderate, and low impact vulnerabilities. The vendor advisory confirms the fix and categorizes the impact of this specific vulnerability as low.
Potential Impact
The impact of this vulnerability is considered low according to the Mozilla advisory. While JIT miscompilation can sometimes lead to security issues such as code execution or memory corruption, no evidence or known exploits have been reported for this vulnerability. It is part of a larger security update that addresses multiple vulnerabilities with varying impacts, but this particular issue is assessed as low impact.
Mitigation Recommendations
A fix for this vulnerability is available in Mozilla Firefox version 152. Users and administrators should update to Firefox 152 or later to remediate this issue. Since the vulnerability is fixed in this official release, no additional mitigation steps are necessary beyond applying the update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:19.456Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-57/","vendor":"Mozilla"}]
Threat ID: 6a314c830b89be6888b4cdca
Added to database: 6/16/2026, 1:15:47 PM
Last enriched: 6/16/2026, 1:32:07 PM
Last updated: 6/16/2026, 5:40:18 PM
Views: 3
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