CVE-2026-16398: Vulnerability in Mozilla Firefox
Site isolation issue in the Graphics component. This vulnerability was fixed in Firefox 153.
AI Analysis
Technical Summary
CVE-2026-16398 describes a site isolation issue within the Graphics component of Mozilla Firefox. Site isolation vulnerabilities can allow processes or content from one site to improperly access or interfere with content from another site, potentially undermining browser security boundaries. This vulnerability was fixed in Firefox 153 as part of a comprehensive security update addressing numerous issues. The vendor advisory categorizes this vulnerability impact as moderate and provides no indication of active exploitation.
Potential Impact
The vulnerability could potentially allow cross-site interference due to improper site isolation in the Graphics component, which may lead to information disclosure or other security boundary violations. However, the impact is assessed as moderate by Mozilla, and no active exploitation has been reported.
Mitigation Recommendations
Users and administrators should update to Firefox version 153 or later, where this vulnerability is fixed. Since the vendor advisory confirms the fix in Firefox 153, applying this official update fully mitigates the issue.
CVE-2026-16398: Vulnerability in Mozilla Firefox
Description
Site isolation issue in the Graphics component. This vulnerability was fixed in Firefox 153.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16398 describes a site isolation issue within the Graphics component of Mozilla Firefox. Site isolation vulnerabilities can allow processes or content from one site to improperly access or interfere with content from another site, potentially undermining browser security boundaries. This vulnerability was fixed in Firefox 153 as part of a comprehensive security update addressing numerous issues. The vendor advisory categorizes this vulnerability impact as moderate and provides no indication of active exploitation.
Potential Impact
The vulnerability could potentially allow cross-site interference due to improper site isolation in the Graphics component, which may lead to information disclosure or other security boundary violations. However, the impact is assessed as moderate by Mozilla, and no active exploitation has been reported.
Mitigation Recommendations
Users and administrators should update to Firefox version 153 or later, where this vulnerability is fixed. Since the vendor advisory confirms the fix in Firefox 153, applying this official update fully mitigates the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:57:27.505Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]
Threat ID: 6a5f6cc12a4a8d5989262930
Added to database: 07/21/2026, 12:57:37 UTC
Last enriched: 07/21/2026, 13:14:24 UTC
Last updated: 07/21/2026, 21:19:23 UTC
Views: 5
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