CVE-2025-47971 is a high-severity vulnerability identified in Microsoft Windows Server 2022 (build 10.0.20348.0) involving a buffer over-read condition in the handling of Virtual Hard Disk (VHDX) files. Specifically, this vulnerability is categorized under CWE-126, which denotes improper buffer handling leading to reading beyond the intended memory bounds. The flaw allows an unauthorized local attacker to exploit the VHDX processing component to elevate privileges on the affected system. The vulnerability requires local access (AV:L) and low attack complexity (AC:L), but no privileges are required initially (PR:N). However, user interaction is necessary (UI:R), indicating that the attacker must induce some action by a legitimate user or process to trigger the exploit. The vulnerability impacts confidentiality, integrity, and availability (all rated high), meaning successful exploitation could lead to full system compromise, unauthorized data access, or disruption of services. The CVSS v3.1 base score is 7.8, reflecting a high severity level. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability's root cause is improper validation or bounds checking when parsing or processing VHDX files, which are commonly used for virtual machine storage in Windows Server environments. Exploiting this flaw could allow attackers to execute arbitrary code with elevated privileges, potentially compromising the entire server and any hosted virtual machines or services.

For European organizations, the impact of CVE-2025-47971 could be significant, especially for enterprises and service providers relying on Windows Server 2022 for virtualization and critical infrastructure. The vulnerability enables local privilege escalation, which could be leveraged by insiders or attackers who have gained limited access to escalate their privileges to system or administrator level. This could lead to unauthorized access to sensitive data, disruption of business-critical applications, and potential lateral movement within corporate networks. Given the widespread adoption of Windows Server 2022 in data centers, cloud environments, and enterprise IT infrastructures across Europe, exploitation could affect sectors such as finance, healthcare, government, and telecommunications. The need for user interaction reduces the likelihood of remote exploitation but does not eliminate risk, as phishing or social engineering could be used to trigger the vulnerability. The absence of known exploits in the wild currently provides a window for proactive mitigation, but the high impact on confidentiality, integrity, and availability necessitates urgent attention.

European organizations should implement a multi-layered mitigation strategy beyond generic patching advice. First, monitor for official security updates from Microsoft and prioritize patch deployment as soon as a fix becomes available. Until patches are released, restrict local access to Windows Server 2022 systems by enforcing strict access controls and limiting administrative privileges to trusted personnel only. Employ application whitelisting and endpoint protection solutions capable of detecting anomalous behavior related to VHDX file handling or privilege escalation attempts. Educate users and administrators about the risks of interacting with untrusted VHDX files or external media, as user interaction is required to trigger the exploit. Implement network segmentation to isolate critical servers and reduce the risk of lateral movement if a local compromise occurs. Additionally, conduct regular security audits and vulnerability assessments focusing on virtualized environments and storage components. Employ logging and monitoring to detect unusual access patterns or privilege escalations on affected systems. Finally, consider disabling or restricting VHDX file handling features if not required for operational purposes, as a temporary risk reduction measure.