CVE-2024-28907 is a high-severity elevation of privilege vulnerability affecting Microsoft Windows Server 2022, 23H2 Edition specifically in the Server Core installation. The vulnerability arises from improper link resolution before file access within the Microsoft Brokering File System component. This is classified under CWE-59, which involves 'Improper Link Resolution Before File Access' or 'Link Following'. Essentially, the system fails to correctly validate symbolic links or junction points before accessing files, allowing an attacker with limited privileges (low-level privileges) to manipulate file system links to escalate their privileges. The vulnerability has a CVSS v3.1 base score of 7.8, indicating a high severity level. The attack vector is local (AV:L), requiring the attacker to have local access with low privileges (PR:L), and no user interaction is needed (UI:N). The complexity is high (AC:H), meaning exploitation requires specific conditions or knowledge. The scope is changed (S:C), indicating that exploitation can affect resources beyond the initially vulnerable component, impacting confidentiality, integrity, and availability at a high level (C:H/I:H/A:H). No known exploits are currently reported in the wild, and no patches have been linked yet. The vulnerability could allow an attacker to gain elevated privileges on affected Windows Server 2022 systems, potentially leading to full system compromise or lateral movement within a network environment. This is particularly critical in server core installations, which are often used in enterprise environments for their reduced attack surface and resource footprint but may be targeted due to their critical role in infrastructure services.

For European organizations, this vulnerability poses a significant risk, especially for enterprises and service providers relying on Windows Server 2022 Server Core installations for critical infrastructure, including data centers, cloud services, and internal network services. Successful exploitation could lead to unauthorized privilege escalation, allowing attackers to execute arbitrary code with elevated rights, access sensitive data, disrupt services, or move laterally within networks. This could result in data breaches, operational downtime, and compromise of critical business applications. Given the high confidentiality, integrity, and availability impact, organizations in sectors such as finance, healthcare, government, and critical infrastructure are particularly at risk. The requirement for local access limits remote exploitation but insider threats or attackers who have gained initial footholds via other means could leverage this vulnerability to deepen their access. The lack of user interaction needed increases the risk of automated or stealthy exploitation once local access is obtained.

1. Immediate deployment of any available patches or security updates from Microsoft once released is critical. 2. Restrict local access to Windows Server 2022 Server Core systems by enforcing strict access controls, including the use of multi-factor authentication and least privilege principles for all users and service accounts. 3. Monitor and audit file system activities, especially symbolic link and junction point creations or modifications, to detect suspicious behavior indicative of exploitation attempts. 4. Employ endpoint detection and response (EDR) solutions capable of identifying privilege escalation techniques and anomalous file system operations. 5. Harden server configurations by disabling unnecessary services and limiting administrative privileges to reduce the attack surface. 6. Conduct regular security assessments and penetration testing focusing on privilege escalation vectors within the environment. 7. Implement network segmentation to limit lateral movement opportunities should an attacker gain local access. 8. Educate system administrators and security teams about this specific vulnerability and encourage vigilance for related indicators of compromise. These measures go beyond generic patching advice by emphasizing proactive monitoring of link-related file system operations and strict local access governance.