Critical Privilege Escalation in Azure AI Face Service (CVE-2025-21415)

Overview

CVE-2025-21415 exposes a critical vulnerability in Microsoft’s Azure AI Face Service, a cloud-based biometric recognition platform. The flaw allows an authorized attacker to bypass authentication through spoofing techniques, resulting in elevation of privilege over the network.

Technical Details

This vulnerability is classified under CWE-290: Authentication Bypass by Spoofing. It enables a threat actor with existing access to manipulate the authentication flow, impersonating users or services without proper verification.

Once successful, the attacker can perform actions with elevated permissions, potentially gaining control over sensitive identity services and AI-powered applications that rely on the Face API. This is particularly concerning in multi-tenant environments and systems integrated with other Azure security mechanisms.

CVSS Score and Severity

According to CVSS v3.1, the vulnerability has a base score of 9.9 (Critical). The vector string is:

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

• Attack Vector: Network
• Attack Complexity: Low
• Privileges Required: Low
• User Interaction: None
• Scope: Changed
• Impact: High on confidentiality, integrity, and availability

These attributes indicate that the attack is easy to execute, requires minimal privileges, and could have cascading effects across service boundaries.

Affected Systems

The vulnerability affects all deployments of the Azure AI Face Service, with no specific versioning due to its nature as a hosted cloud service.

Mitigation and Recommendations

• Microsoft has issued updates and mitigations through the Azure platform. Customers should verify that their instance of the Face Service is operating with the latest security patches.
• Audit access control and authentication logs for anomalies related to identity spoofing or privilege escalation.
• Ensure strict role-based access controls (RBAC) and multi-factor authentication (MFA) are in place across dependent Azure resources.

Conclusion

CVE-2025-21415 is a stark reminder that even cloud-native AI services can be susceptible to privilege escalation via authentication bypass. Organizations using Azure’s Face API should act promptly to secure their deployments and validate trust boundaries within their identity architectures.

For more details, refer to Microsoft’s official advisory: MSRC: CVE-2025-21415