CVE-2024-30085 is a heap-based buffer overflow vulnerability classified under CWE-122, found in the Windows Cloud Files Mini Filter Driver component of Microsoft Windows 11 version 21H2 (build 22000.0). This vulnerability allows an attacker with limited privileges (local authenticated user) to perform an elevation of privilege attack by exploiting improper handling of memory buffers within the mini filter driver. The flaw arises when the driver processes certain inputs or operations that cause it to overwrite heap memory, potentially leading to arbitrary code execution with elevated privileges. The vulnerability does not require user interaction and has a low attack complexity, but it does require local access with some privileges. The CVSS v3.1 score of 7.8 reflects high impact on confidentiality, integrity, and availability, as successful exploitation could allow an attacker to gain SYSTEM-level privileges, compromise system security, and execute malicious code. Although no known exploits are currently reported in the wild, the vulnerability is publicly disclosed, increasing the risk of future exploitation. The Windows Cloud Files Mini Filter Driver is involved in managing cloud file synchronization and caching, making this vulnerability relevant for environments using OneDrive or similar cloud file services integrated into Windows 11. The vulnerability was reserved in March 2024 and published in June 2024, with no patch links currently available, indicating that organizations should monitor for official updates from Microsoft and prepare for rapid deployment.

For European organizations, this vulnerability poses a significant risk due to the widespread adoption of Windows 11 version 21H2 in enterprise and government environments. Successful exploitation could lead to privilege escalation, allowing attackers to bypass security controls, access sensitive data, disrupt operations, or deploy ransomware and other malware with elevated privileges. Critical sectors such as finance, healthcare, energy, and public administration could face severe operational and reputational damage. The integration of cloud file services in Windows 11 means that organizations relying on OneDrive or similar services could see increased attack surfaces. The lack of required user interaction and the relatively low complexity of exploitation increase the likelihood of attacks once exploit code becomes available. Additionally, the vulnerability could be leveraged as part of multi-stage attacks, where initial access is gained through other means, and this flaw is used to escalate privileges and move laterally within networks. European organizations with strict data protection regulations (e.g., GDPR) must consider the potential for data breaches and compliance violations resulting from exploitation.

Organizations should prioritize the following mitigations: 1) Monitor Microsoft security advisories closely and apply patches immediately once released to address CVE-2024-30085. 2) Implement strict local access controls and limit user privileges to the minimum necessary to reduce the risk of local exploitation. 3) Employ endpoint detection and response (EDR) solutions to monitor for unusual behavior indicative of privilege escalation attempts, especially related to the Cloud Files Mini Filter Driver. 4) Restrict or monitor the use of cloud file synchronization features if feasible, or apply group policies to control OneDrive and related services. 5) Conduct regular security audits and vulnerability assessments focusing on Windows 11 systems to identify unpatched or vulnerable hosts. 6) Educate IT staff and users about the risks of local privilege escalation vulnerabilities and the importance of timely patching. 7) Use application whitelisting and exploit mitigation technologies such as Control Flow Guard (CFG) and Data Execution Prevention (DEP) to reduce the impact of memory corruption vulnerabilities. 8) Segment networks to limit lateral movement opportunities if an attacker gains local access. These measures, combined with rapid patch deployment, will significantly reduce the risk posed by this vulnerability.