CVE-2024-38054 is a high-severity heap-based buffer overflow vulnerability (CWE-122) affecting the Kernel Streaming WOW Thunk Service Driver in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability allows an attacker with limited privileges (local access with low privileges) to escalate their privileges to SYSTEM level by exploiting improper handling of kernel streaming operations. The flaw resides in the way the vulnerable driver processes certain inputs, leading to a heap-based buffer overflow that can corrupt memory, potentially allowing arbitrary code execution with elevated privileges. The vulnerability requires local access and does not need user interaction, but the attacker must have some level of authenticated access (PR:L). The CVSS v3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability (all rated high), with low attack complexity and no user interaction required. Although no known exploits are currently reported in the wild, the vulnerability poses a significant risk due to the potential for privilege escalation, which can be leveraged to fully compromise affected systems. The absence of published patches at the time of this report increases the urgency for mitigation and monitoring. This vulnerability specifically targets Windows 10 Version 1809, an older but still in-use version of Windows 10, which may be present in enterprise environments that have not upgraded to more recent versions.

For European organizations, this vulnerability presents a critical risk primarily in environments where Windows 10 Version 1809 is still deployed, such as legacy systems or specialized industrial and governmental setups that have delayed OS upgrades. Successful exploitation could allow attackers to gain SYSTEM-level privileges from a low-privileged local account, enabling full control over affected machines. This could lead to unauthorized access to sensitive data, disruption of services, installation of persistent malware, and lateral movement within networks. Given the high confidentiality, integrity, and availability impacts, organizations handling critical infrastructure, financial data, or personal data protected under GDPR could face severe operational and compliance consequences. The local access requirement somewhat limits remote exploitation, but insider threats or attackers who have gained initial footholds via other means could leverage this vulnerability to escalate privileges and deepen their access. The lack of known exploits currently reduces immediate risk but does not eliminate the threat, especially as exploit development could follow soon after disclosure. The absence of patches necessitates interim mitigations to reduce exposure.

European organizations should prioritize the following specific mitigation steps: 1) Identify and inventory all systems running Windows 10 Version 1809 to assess exposure. 2) Where possible, upgrade affected systems to a supported and patched version of Windows 10 or later, as this vulnerability is specific to version 1809. 3) Implement strict access controls to limit local user accounts with low privileges from accessing sensitive systems, reducing the attack surface. 4) Employ application whitelisting and endpoint detection and response (EDR) solutions to monitor for suspicious activity indicative of privilege escalation attempts. 5) Restrict the use of kernel streaming features or related services if feasible, or apply group policies to limit their usage. 6) Increase monitoring and logging of local privilege escalation attempts and unusual kernel driver activity. 7) Educate IT staff and users about the risks of local privilege escalation vulnerabilities and the importance of timely patching and system upgrades. 8) Stay alert for official patches or updates from Microsoft and apply them promptly once available. These targeted actions go beyond generic advice by focusing on the specific affected version, attack vector, and exploitation requirements.