CVE-2025-53802 is a high-severity use-after-free vulnerability (CWE-416) found in the Windows Bluetooth Service component of Microsoft Windows Server 2022 (build 10.0.20348.0). This vulnerability allows an authorized local attacker to elevate privileges by exploiting improper memory management in the Bluetooth service. Specifically, the flaw arises when the service attempts to access memory that has already been freed, leading to undefined behavior that can be leveraged to execute arbitrary code with elevated privileges. The attacker must have local access and some level of privileges (low privileges) but does not require user interaction to exploit this vulnerability. The CVSS v3.1 base score is 7.0, reflecting high severity, with attack vector local (AV:L), attack complexity high (AC:H), privileges required low (PR:L), no user interaction (UI:N), unchanged scope (S:U), and high impact on confidentiality, integrity, and availability (C:H/I:H/A:H). No known exploits are currently reported in the wild, and no patches have been linked yet, indicating that mitigation may rely on vendor updates once available. The vulnerability could allow attackers to gain SYSTEM-level privileges from a lower-privileged account, potentially compromising the entire server environment.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and service providers relying on Windows Server 2022 for critical infrastructure and services. Successful exploitation could lead to full system compromise, allowing attackers to access sensitive data, disrupt services, or move laterally within networks. Given the Bluetooth Service is involved, environments where Bluetooth is enabled on servers could be particularly vulnerable. The elevation of privilege from a low-privileged user to SYSTEM could facilitate deployment of ransomware, espionage, or sabotage attacks. This is especially concerning for sectors such as finance, healthcare, government, and critical infrastructure in Europe, where Windows Server 2022 adoption is substantial. The lack of known exploits currently provides a window for proactive mitigation, but the high impact on confidentiality, integrity, and availability means organizations must prioritize addressing this vulnerability promptly to avoid potential severe breaches.

European organizations should immediately audit their Windows Server 2022 deployments to identify systems running the affected build (10.0.20348.0) with Bluetooth Service enabled. Until a patch is released, consider disabling the Bluetooth Service on servers where it is not essential to reduce the attack surface. Implement strict access controls to limit local user accounts with low privileges, minimizing the pool of potential attackers. Employ application whitelisting and endpoint detection and response (EDR) solutions to monitor for suspicious activity indicative of exploitation attempts. Regularly review and tighten group policies related to local user permissions. Once Microsoft releases an official patch, prioritize its deployment across all affected systems. Additionally, conduct internal penetration testing focused on privilege escalation vectors to validate the effectiveness of mitigations. Maintain up-to-date backups and incident response plans to quickly recover from potential compromises.