CVE-2026-16396: Vulnerability in Mozilla Firefox
Privilege escalation in WebExtensions. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
AI Analysis
Technical Summary
CVE-2026-16396 is a privilege escalation vulnerability affecting the WebExtensions component in Firefox. It was fixed in Firefox 153 and Firefox ESR 140.13. The Mozilla advisory classifies the impact as moderate and confirms that the vulnerability allows escalation of privileges within the browser. The advisory is part of a broader security update addressing multiple vulnerabilities. No active exploitation has been observed, but the fix is available and should be applied.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser environment, potentially bypassing security restrictions imposed on WebExtensions. This could lead to unauthorized actions or access within the browser context.
Mitigation Recommendations
Apply the official security updates provided by Mozilla by upgrading to Firefox 153 or later, or Firefox ESR 140.13 or later. These versions contain the fix for this vulnerability. No additional mitigation steps are required beyond applying the official patches.
CVE-2026-16396: Vulnerability in Mozilla Firefox
Description
Privilege escalation in WebExtensions. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
CVSS v3.1
Score 8.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16396 is a privilege escalation vulnerability affecting the WebExtensions component in Firefox. It was fixed in Firefox 153 and Firefox ESR 140.13. The Mozilla advisory classifies the impact as moderate and confirms that the vulnerability allows escalation of privileges within the browser. The advisory is part of a broader security update addressing multiple vulnerabilities. No active exploitation has been observed, but the fix is available and should be applied.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escalate privileges within the Firefox browser environment, potentially bypassing security restrictions imposed on WebExtensions. This could lead to unauthorized actions or access within the browser context.
Mitigation Recommendations
Apply the official security updates provided by Mozilla by upgrading to Firefox 153 or later, or Firefox ESR 140.13 or later. These versions contain the fix for this vulnerability. No additional mitigation steps are required beyond applying the official patches.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-97fr-g29v-hhwf
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-16396"]
- Ecosystems
- []
- Database Specific Severity
- null
- Cvss Version
- null
Threat ID: 6a5fd1561010f89cc21c982b
Added to database: 07/21/2026, 20:06:46 UTC
Last enriched: 07/22/2026, 17:41:04 UTC
Last updated: 08/26/2026, 22:52:08 UTC
Views: 67
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