CVE-2025-21385 is a high-severity Server-Side Request Forgery (SSRF) vulnerability identified in Microsoft Purview, a cloud-based data governance and compliance solution widely used for managing and protecting organizational data. SSRF vulnerabilities allow an attacker to abuse a vulnerable server to send crafted requests to internal or external systems that the server can access, potentially bypassing network access controls. In this case, the vulnerability permits an authorized attacker—meaning the attacker must have some level of legitimate access—to coerce Microsoft Purview into making unauthorized network requests. This can lead to the disclosure of sensitive information over the network, impacting confidentiality, integrity, and availability. The CVSS 3.1 base score of 8.8 reflects the high impact on confidentiality, integrity, and availability, with low attack complexity and no user interaction required. The vulnerability does not require user interaction but does require privileges (PR:L), indicating that the attacker must be an authenticated user with some level of access to the system. The scope is unchanged (S:U), meaning the vulnerability affects the same security scope. Although no known exploits are currently reported in the wild, the potential for exploitation exists given the nature of SSRF vulnerabilities and the criticality of Microsoft Purview in enterprise environments. No specific affected versions were listed, suggesting the vulnerability may impact multiple or all current versions of Microsoft Purview. No patches were linked at the time of reporting, indicating organizations should monitor for updates and advisories from Microsoft.

For European organizations, the impact of this SSRF vulnerability in Microsoft Purview could be significant. Microsoft Purview is commonly used by enterprises for data governance, compliance, and risk management, often handling sensitive personal data subject to strict regulations such as GDPR. Exploitation could lead to unauthorized disclosure of internal network information or sensitive data, potentially resulting in data breaches, regulatory non-compliance, and reputational damage. The ability to send arbitrary requests from the server could also facilitate lateral movement within internal networks or access to internal services not exposed externally, increasing the risk of further compromise. Given the high confidentiality, integrity, and availability impacts, organizations could face operational disruptions and legal consequences. The requirement for an authenticated attacker limits exposure to insider threats or compromised accounts but does not eliminate risk, especially in large organizations with many users and complex access controls. The lack of known exploits currently reduces immediate risk but does not preclude future exploitation attempts, especially as threat actors often target widely used Microsoft products.

1. Immediate mitigation should focus on restricting and monitoring access to Microsoft Purview, ensuring that only necessary users have authenticated access, and applying the principle of least privilege to minimize the risk posed by compromised accounts. 2. Network segmentation and firewall rules should be reviewed and tightened to limit the ability of Microsoft Purview to make arbitrary network requests, especially to sensitive internal resources. 3. Implement strict egress filtering and monitoring of outbound requests from Microsoft Purview to detect and block suspicious or unauthorized network traffic indicative of SSRF exploitation attempts. 4. Enable comprehensive logging and alerting on Microsoft Purview activities to detect anomalous behavior that could signal exploitation attempts. 5. Stay current with Microsoft security advisories and apply patches or updates as soon as they become available to remediate the vulnerability. 6. Conduct internal security assessments and penetration testing focused on SSRF vectors within Microsoft Purview deployments to identify and remediate potential attack paths. 7. Educate administrators and users about the risks of SSRF and the importance of safeguarding credentials and access to Microsoft Purview.