CVE-2026-16363: Vulnerability in Mozilla Firefox
CVE-2026-16363 is a critical vulnerability in Mozilla Firefox involving a Just-In-Time (JIT) miscompilation issue in the JavaScript WebAssembly component. This flaw could lead to high impact consequences including confidentiality, integrity, and availability breaches. The vulnerability affects Firefox versions prior to 153 and Firefox ESR versions prior to 140.13. Mozilla has released official fixes in Firefox 153 and Firefox ESR 140.13. There are no known exploits in the wild at this time. The issue is part of a broader set of high-impact security fixes addressed simultaneously by Mozilla.
AI Analysis
Technical Summary
This vulnerability is a JIT miscompilation in the JavaScript WebAssembly component of Mozilla Firefox, identified as CVE-2026-16363. It was reported by Nebula Security and is classified with a CVSS 3.1 score of 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The vulnerability could allow an attacker to compromise confidentiality, integrity, and availability of the affected system. Mozilla fixed this issue in Firefox 153 and Firefox ESR 140.13. The vendor advisory confirms the fix and provides detailed references to the bug report (Bug 2047689). There are no confirmed active exploits in the wild.
Potential Impact
The vulnerability allows potential remote attackers to exploit a JIT miscompilation flaw in the WebAssembly component, which can lead to complete compromise of confidentiality, integrity, and availability of the affected Firefox browser. Given the CVSS score of 9.8, the impact is critical, meaning successful exploitation could result in arbitrary code execution or other severe consequences without requiring user interaction or privileges.
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. There are no additional mitigations required beyond applying the official patches. Patch status is confirmed by the vendor advisory.
CVE-2026-16363: Vulnerability in Mozilla Firefox
Description
CVE-2026-16363 is a critical vulnerability in Mozilla Firefox involving a Just-In-Time (JIT) miscompilation issue in the JavaScript WebAssembly component. This flaw could lead to high impact consequences including confidentiality, integrity, and availability breaches. The vulnerability affects Firefox versions prior to 153 and Firefox ESR versions prior to 140.13. Mozilla has released official fixes in Firefox 153 and Firefox ESR 140.13. There are no known exploits in the wild at this time. The issue is part of a broader set of high-impact security fixes addressed simultaneously by Mozilla.
CVSS v3.1
Score 9.8critical
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability is a JIT miscompilation in the JavaScript WebAssembly component of Mozilla Firefox, identified as CVE-2026-16363. It was reported by Nebula Security and is classified with a CVSS 3.1 score of 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. The vulnerability could allow an attacker to compromise confidentiality, integrity, and availability of the affected system. Mozilla fixed this issue in Firefox 153 and Firefox ESR 140.13. The vendor advisory confirms the fix and provides detailed references to the bug report (Bug 2047689). There are no confirmed active exploits in the wild.
Potential Impact
The vulnerability allows potential remote attackers to exploit a JIT miscompilation flaw in the WebAssembly component, which can lead to complete compromise of confidentiality, integrity, and availability of the affected Firefox browser. Given the CVSS score of 9.8, the impact is critical, meaning successful exploitation could result in arbitrary code execution or other severe consequences without requiring user interaction or privileges.
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. There are no additional mitigations required beyond applying the official patches. Patch status is confirmed by the vendor advisory.
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: 07/30/2026, 10:54:08 UTC
Last updated: 09/04/2026, 10:52:07 UTC
Views: 98
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