CVE-2025-10531: Vulnerability in Mozilla Firefox
Mitigation bypass in the Web Compatibility: Tooling component. This vulnerability was fixed in Firefox 143 and Thunderbird 143.
AI Analysis
Technical Summary
This vulnerability involves a mitigation bypass in the Web Compatibility: Tooling component of Mozilla Firefox. It was reported by Nikolaos Mourousias and assigned CVE-2025-10531. The issue was fixed in Firefox 143 and Thunderbird 143. The CVSS v3.1 base score is 5.4 (medium severity), with attack vector network, low attack complexity, no privileges required, user interaction required, and impacts on confidentiality and integrity but not availability. The vendor advisory explicitly states the vulnerability is fixed in Firefox 143 and Thunderbird 143.
Potential Impact
The vulnerability allows bypassing mitigation controls in the Web Compatibility: Tooling component, potentially leading to partial confidentiality and integrity impacts. However, the impact is rated moderate by Mozilla, and no known exploits have been observed in the wild. The medium CVSS score reflects a moderate risk level.
Mitigation Recommendations
A fix for this vulnerability is available and has been incorporated in Mozilla Firefox 143 and Thunderbird 143. Users and administrators should update to these versions or later to remediate the issue. Since the vendor advisory confirms the fix, no additional mitigation steps are required beyond applying the official update.
CVE-2025-10531: Vulnerability in Mozilla Firefox
Description
Mitigation bypass in the Web Compatibility: Tooling component. This vulnerability was fixed in Firefox 143 and Thunderbird 143.
CVSS v3.1
Score 5.4medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a mitigation bypass in the Web Compatibility: Tooling component of Mozilla Firefox. It was reported by Nikolaos Mourousias and assigned CVE-2025-10531. The issue was fixed in Firefox 143 and Thunderbird 143. The CVSS v3.1 base score is 5.4 (medium severity), with attack vector network, low attack complexity, no privileges required, user interaction required, and impacts on confidentiality and integrity but not availability. The vendor advisory explicitly states the vulnerability is fixed in Firefox 143 and Thunderbird 143.
Potential Impact
The vulnerability allows bypassing mitigation controls in the Web Compatibility: Tooling component, potentially leading to partial confidentiality and integrity impacts. However, the impact is rated moderate by Mozilla, and no known exploits have been observed in the wild. The medium CVSS score reflects a moderate risk level.
Mitigation Recommendations
A fix for this vulnerability is available and has been incorporated in Mozilla Firefox 143 and Thunderbird 143. Users and administrators should update to these versions or later to remediate the issue. Since the vendor advisory confirms the fix, no additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-09-16T06:48:41.514Z
- State
- PUBLISHED
Threat ID: 68c958bfff7c553b3ddd1ee4
Added to database: 09/16/2025, 12:31:59 UTC
Last enriched: 04/14/2026, 11:33:53 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 210
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