CVE-2025-0237: Vulnerability in Mozilla Firefox
The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
AI Analysis
Technical Summary
The WebChannel API in Mozilla Firefox, which facilitates inter-process communication, did not properly validate the sending principal, accepting the principal as provided rather than verifying it. This flaw could have been exploited to escalate privileges within the browser environment. Mozilla fixed this vulnerability in Firefox 134 and Firefox ESR 128.6 as part of their January 2025 security updates. The CVSS v3.1 base score is 5.4 (medium severity), reflecting network attack vector, low attack complexity, required privileges, no user interaction, and limited confidentiality and integrity impacts.
Potential Impact
Successful exploitation of this vulnerability could have allowed an attacker to escalate privileges within the Firefox browser by exploiting the WebChannel API's failure to validate the sending principal. This could lead to unauthorized actions or access within the browser context. However, there are no reports of active exploitation in the wild. The impact is rated moderate by Mozilla and the CVSS score supports this assessment.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 134 and Firefox ESR 128.6. Users and administrators should update to these versions or later to remediate the issue. Since this is a client-side application vulnerability, applying the official update is the recommended and effective mitigation. No additional mitigation steps are indicated by the vendor advisory.
CVE-2025-0237: Vulnerability in Mozilla Firefox
Description
The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The WebChannel API in Mozilla Firefox, which facilitates inter-process communication, did not properly validate the sending principal, accepting the principal as provided rather than verifying it. This flaw could have been exploited to escalate privileges within the browser environment. Mozilla fixed this vulnerability in Firefox 134 and Firefox ESR 128.6 as part of their January 2025 security updates. The CVSS v3.1 base score is 5.4 (medium severity), reflecting network attack vector, low attack complexity, required privileges, no user interaction, and limited confidentiality and integrity impacts.
Potential Impact
Successful exploitation of this vulnerability could have allowed an attacker to escalate privileges within the Firefox browser by exploiting the WebChannel API's failure to validate the sending principal. This could lead to unauthorized actions or access within the browser context. However, there are no reports of active exploitation in the wild. The impact is rated moderate by Mozilla and the CVSS score supports this assessment.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 134 and Firefox ESR 128.6. Users and administrators should update to these versions or later to remediate the issue. Since this is a client-side application vulnerability, applying the official update is the recommended and effective mitigation. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-01-06T14:48:59.270Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6909325c35043901e83099ee
Added to database: 11/3/2025, 10:53:16 PM
Last enriched: 4/14/2026, 11:32:18 AM
Last updated: 5/9/2026, 7:27:21 AM
Views: 98
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