CVE-2025-24995 is a heap-based buffer overflow vulnerability identified in the Kernel Streaming WOW Thunk Service Driver component of Microsoft Windows 10 Version 1809 (build 10.0.17763.0). This vulnerability is classified under CWE-122, indicating improper handling of memory buffers leading to overflow conditions on the heap. The flaw allows an authorized local attacker—meaning the attacker must have some level of access to the system—to execute a privilege escalation attack. By exploiting this vulnerability, the attacker can overwrite memory in the kernel space, potentially gaining elevated privileges such as SYSTEM-level access. This elevation of privilege can allow the attacker to bypass security restrictions, execute arbitrary code with high privileges, and compromise system integrity and confidentiality. The vulnerability does not require user interaction but does require local access with limited privileges. The CVSS v3.1 base score is 7.8 (high severity), reflecting the significant impact on confidentiality, integrity, and availability, combined with relatively low attack complexity and the requirement for local privileges but no user interaction. There are no known exploits in the wild at the time of publication, and no official patches have been linked yet. The vulnerability was reserved in late January 2025 and published in March 2025, indicating recent discovery and disclosure.

For European organizations, this vulnerability poses a significant risk, especially in environments where Windows 10 Version 1809 is still in use. Many enterprises, government agencies, and critical infrastructure operators in Europe may still run legacy systems due to compatibility or operational constraints. An attacker with local access—such as a malicious insider, compromised user account, or attacker who has gained initial foothold via other means—could leverage this vulnerability to escalate privileges and gain full control over affected systems. This could lead to data breaches, disruption of services, installation of persistent malware, or lateral movement within networks. The impact is particularly critical for sectors with high-value data or critical operations, such as finance, healthcare, manufacturing, and public administration. Given the high confidentiality, integrity, and availability impact, exploitation could result in significant operational disruption and regulatory consequences under GDPR and other European data protection laws.

Organizations should prioritize upgrading or patching affected systems as soon as official fixes become available from Microsoft. Until patches are released, practical mitigations include: 1) Restricting local access to systems running Windows 10 Version 1809 by enforcing strict access controls and monitoring for unauthorized logins; 2) Employing application whitelisting and endpoint detection and response (EDR) solutions to detect anomalous behavior indicative of privilege escalation attempts; 3) Disabling or restricting the use of the Kernel Streaming WOW Thunk Service Driver if feasible, or applying system hardening measures to reduce attack surface; 4) Ensuring that least privilege principles are enforced so that users and processes operate with minimal necessary permissions; 5) Conducting regular audits and monitoring for suspicious activity related to privilege escalation; 6) Planning and executing migration to supported Windows versions that receive ongoing security updates to reduce exposure to legacy vulnerabilities.