CVE-2025-54105 is a race condition vulnerability classified under CWE-362 affecting the Microsoft Brokering File System in Windows Server 2025 Server Core installations (version 10.0.26100.0). The vulnerability stems from improper synchronization during concurrent execution of shared resources, which can be exploited by an authorized local attacker to elevate privileges. This race condition allows the attacker to manipulate the timing of resource access, potentially bypassing security controls and gaining higher privileges than intended. The CVSS v3.1 base score is 7.0, reflecting a high severity due to the potential for full compromise of confidentiality, integrity, and availability. The attack vector is local (AV:L), requiring low privileges (PR:L) but high attack complexity (AC:H), and no user interaction (UI:N). The scope remains unchanged (S:U). Although no known exploits are currently reported in the wild, the vulnerability poses a significant risk to environments running the affected Windows Server version, especially in Server Core configurations where minimal UI and services are present. The vulnerability was reserved in July 2025 and published in September 2025, with no patches currently linked, indicating organizations must prepare for imminent remediation. The race condition could lead to unauthorized code execution or system control escalation, making it critical for administrators to monitor and restrict local access and prepare for patch deployment.

For European organizations, the impact of CVE-2025-54105 is substantial. Windows Server 2025 Server Core is likely deployed in enterprise data centers, cloud environments, and critical infrastructure systems across Europe. Successful exploitation could allow attackers to escalate privileges locally, potentially leading to full system compromise, unauthorized data access, disruption of services, and lateral movement within networks. This could affect confidentiality of sensitive data, integrity of system configurations, and availability of critical services. Sectors such as finance, healthcare, government, and telecommunications, which heavily rely on Windows Server environments, are particularly at risk. The requirement for local access limits remote exploitation but insider threats or compromised user accounts could leverage this vulnerability. The absence of known exploits currently provides a window for proactive defense, but the high severity and potential for privilege escalation necessitate urgent attention. Failure to address this vulnerability could result in regulatory non-compliance under GDPR if personal data is compromised, leading to legal and financial repercussions.

1. Monitor for official Microsoft patches and apply them immediately upon release to address the race condition. 2. Restrict local access to Windows Server 2025 Server Core systems by enforcing strict access controls, limiting administrative privileges, and using just-in-time access models. 3. Implement enhanced logging and monitoring to detect unusual privilege escalation attempts or race condition exploitation patterns. 4. Employ application whitelisting and endpoint detection and response (EDR) solutions to identify and block suspicious local activities. 5. Conduct regular security audits and vulnerability assessments focusing on concurrency and synchronization issues in critical systems. 6. Use virtualization or containerization to isolate critical services and reduce the attack surface. 7. Educate system administrators and users about the risks of local privilege escalation and the importance of safeguarding credentials. 8. Prepare incident response plans specifically addressing local privilege escalation scenarios to minimize impact if exploitation occurs.