CVE-2026-16363: Vulnerability in Mozilla Firefox
JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.
AI Analysis
Technical Summary
CVE-2026-16363 is a vulnerability in Mozilla Firefox's JavaScript engine, specifically a JIT miscompilation flaw in the WebAssembly component. This miscompilation could lead to incorrect code execution within the browser's WebAssembly environment. Mozilla fixed this vulnerability in Firefox 153 and Firefox ESR 140.13 as part of a security advisory addressing multiple high-impact bugs. The advisory confirms the impact as high and provides references to the bug report (Bug 2047689). No active exploitation in the wild is currently known.
Potential Impact
The vulnerability could cause incorrect execution of WebAssembly code due to JIT miscompilation, which may lead to security issues such as privilege escalation or sandbox escape if exploited. The vendor rates the impact as high. However, there are no known active exploits in the wild for this vulnerability at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153 and Firefox ESR 140.13. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. Since this is not a cloud service, patching the client software is required. There is no indication from the vendor advisory that additional mitigation steps are necessary beyond applying the official update.
CVE-2026-16363: Vulnerability in Mozilla Firefox
Description
JIT miscompilation in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16363 is a vulnerability in Mozilla Firefox's JavaScript engine, specifically a JIT miscompilation flaw in the WebAssembly component. This miscompilation could lead to incorrect code execution within the browser's WebAssembly environment. Mozilla fixed this vulnerability in Firefox 153 and Firefox ESR 140.13 as part of a security advisory addressing multiple high-impact bugs. The advisory confirms the impact as high and provides references to the bug report (Bug 2047689). No active exploitation in the wild is currently known.
Potential Impact
The vulnerability could cause incorrect execution of WebAssembly code due to JIT miscompilation, which may lead to security issues such as privilege escalation or sandbox escape if exploited. The vendor rates the impact as high. However, there are no known active exploits in the wild for this vulnerability at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153 and Firefox ESR 140.13. Users and administrators should update affected Firefox installations to these versions or later to remediate the issue. Since this is not a cloud service, patching the client software is required. There is no indication from the vendor advisory that additional mitigation steps are necessary beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:56:13.042Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]
Threat ID: 6a5f6cbb2a4a8d598926250d
Added to database: 07/21/2026, 12:57:31 UTC
Last enriched: 07/21/2026, 13:42:28 UTC
Last updated: 07/21/2026, 21:18:38 UTC
Views: 4
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