CVE-2025-64663 is a Server-Side Request Forgery (SSRF) vulnerability classified under CWE-918 that affects Microsoft Azure Cognitive Service for Language, particularly the Custom Question Answering component. SSRF vulnerabilities allow attackers to induce the server to make unintended requests to internal or external systems, potentially bypassing network access controls. In this case, the vulnerability enables an elevation of privilege, meaning an attacker with some level of access can leverage SSRF to gain higher privileges or access sensitive internal resources that should be protected. The CVSS v3.1 score of 9.9 reflects the critical nature of this flaw, with network attack vector (AV:N), low attack complexity (AC:L), requiring privileges (PR:L) but no user interaction (UI:N), and complete impact on confidentiality, integrity, and availability (C:H/I:H/A:H). The scope is changed (S:C), indicating that exploitation affects resources beyond the initially vulnerable component. Although no public exploits are currently known, the vulnerability's characteristics suggest it could be exploited to access internal metadata services, internal APIs, or other protected resources within Azure's infrastructure, potentially leading to data exfiltration, service disruption, or further compromise. The lack of specified affected versions suggests the vulnerability may impact multiple or all current versions of the service. The vulnerability was reserved in early November 2025 and published in mid-December 2025, indicating recent discovery and disclosure. No patches are listed yet, emphasizing the need for vigilance and proactive mitigation.

For European organizations, the impact of CVE-2025-64663 could be severe. Many enterprises and public sector entities in Europe rely on Microsoft Azure Cognitive Services for AI-driven language processing tasks, including customer support automation, document analysis, and knowledge management. Exploitation of this SSRF vulnerability could lead to unauthorized access to sensitive data, including personal data protected under GDPR, resulting in significant regulatory and reputational consequences. The elevation of privilege aspect means attackers could gain control over or disrupt critical AI services, impacting business continuity and operational integrity. Additionally, SSRF can be a pivot point for lateral movement within cloud environments, increasing the risk of broader compromise. Given the criticality of the vulnerability and the widespread use of Azure in Europe, the potential for data breaches, service outages, and compliance violations is high, especially in sectors like finance, healthcare, and government where data sensitivity and service availability are paramount.

Organizations should immediately review their use of Azure Cognitive Service for Language and implement compensating controls until a patch is available. These include restricting network egress and ingress rules to limit the service's ability to make arbitrary outbound requests, employing strict firewall and virtual network service endpoints to isolate the service, and monitoring logs for unusual request patterns indicative of SSRF attempts. Privilege management should be tightened to minimize the number of users or services with elevated permissions that could exploit this vulnerability. Implementing Web Application Firewalls (WAF) with SSRF detection rules can help detect and block malicious requests. Once Microsoft releases a patch, organizations must prioritize timely deployment. Additionally, conducting internal audits and penetration tests focusing on SSRF vectors in cloud services can help identify residual risks. Finally, organizations should prepare incident response plans specific to cloud service compromises to quickly contain and remediate any exploitation.