CVE-2025-24058 is a high-severity vulnerability identified in the Microsoft Windows 10 Version 1809 operating system, specifically within the Desktop Window Manager (DWM) Core Library. The root cause of this vulnerability is improper input validation (classified under CWE-20), which allows an authorized local attacker to escalate their privileges on the affected system. The vulnerability requires the attacker to have some level of local access (low attack vector) and privileges (low privileges), but does not require user interaction to exploit. Exploitation of this flaw could allow an attacker to gain higher privileges, potentially SYSTEM-level, thereby compromising the confidentiality, integrity, and availability of the system. The CVSS v3.1 base score is 7.8, reflecting high severity with impacts rated as high on confidentiality, integrity, and availability. The vulnerability is present in Windows 10 Version 1809 build 10.0.17763.0, an older but still in-use version of Windows 10. No public exploits are currently known in the wild, and no official patches have been linked yet, though the vulnerability has been published and assigned by Microsoft and enriched by CISA. Given the nature of the DWM Core Library, which manages graphical user interface elements, improper input validation here could allow malicious code or commands to be processed in a way that elevates privileges beyond the attacker's current rights. This could lead to full system compromise if exploited successfully.

For European organizations, this vulnerability poses a significant risk, especially for those still operating legacy systems running Windows 10 Version 1809. Privilege escalation vulnerabilities can be leveraged by attackers who have gained initial foothold through other means (e.g., phishing, malware) to gain full control over critical systems. This can lead to data breaches involving sensitive personal data protected under GDPR, disruption of business operations, and potential ransomware deployment. The high impact on confidentiality, integrity, and availability means that attackers could exfiltrate data, alter system configurations, or cause system outages. Industries with high reliance on Windows 10 1809, such as manufacturing, healthcare, and government agencies, could face operational disruptions and regulatory penalties. The lack of known exploits in the wild currently provides a window for mitigation, but the presence of this vulnerability in an older OS version means many organizations may have delayed patching or upgrading, increasing exposure risk.

European organizations should prioritize identifying and inventorying all systems running Windows 10 Version 1809 (build 10.0.17763.0). Immediate mitigation steps include: 1) Applying any available security updates or patches from Microsoft as soon as they are released. 2) If patches are not yet available, implement compensating controls such as restricting local user privileges, enforcing strict access controls, and monitoring for unusual local privilege escalation attempts. 3) Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and prevent exploitation attempts targeting the DWM Core Library. 4) Encourage or enforce upgrading to newer, supported versions of Windows 10 or Windows 11 where this vulnerability is not present. 5) Conduct user awareness training to reduce the risk of initial compromise that could lead to exploitation of this vulnerability. 6) Regularly audit and monitor logs for signs of privilege escalation or anomalous behavior related to DWM processes. These targeted steps go beyond generic patching advice and focus on minimizing attack surface and early detection.