CVE-2025-49725 is a high-severity use-after-free vulnerability (CWE-416) affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw exists within the Windows Notification component, where improper handling of memory leads to a use-after-free condition. This vulnerability allows an authorized local attacker with limited privileges to execute code in a higher privilege context, effectively enabling privilege escalation. The attacker does not require user interaction to exploit this vulnerability, and the attack complexity is low, meaning exploitation is feasible with minimal effort once local access is obtained. The vulnerability impacts confidentiality, integrity, and availability, as it can lead to arbitrary code execution with elevated privileges, potentially allowing full system compromise. Although no known exploits are currently observed in the wild, the vulnerability has been publicly disclosed and assigned a CVSS v3.1 base score of 7.8, reflecting its high impact and exploitability. No patches or mitigation updates are currently linked, indicating that affected organizations should prioritize monitoring and interim mitigations until official fixes are released.

For European organizations, this vulnerability poses a significant risk, especially in environments where Windows 10 Version 1809 is still in use. Successful exploitation could allow attackers who have gained limited local access—such as through phishing, insider threats, or other initial footholds—to escalate privileges and gain full control over affected systems. This can lead to data breaches, disruption of critical services, and lateral movement within corporate networks. Sectors with high reliance on legacy Windows 10 systems, including government, healthcare, finance, and critical infrastructure, are particularly vulnerable. The ability to elevate privileges without user interaction increases the threat level, as automated or stealthy attacks become feasible. Given the lack of known exploits in the wild, proactive mitigation is essential to prevent future exploitation, especially considering the potential for attackers to develop exploits rapidly following public disclosure.

1. Immediate assessment and inventory of all systems running Windows 10 Version 1809 (build 10.0.17763.0) to identify affected endpoints. 2. Apply any available security updates or patches from Microsoft as soon as they are released; monitor official Microsoft security advisories closely. 3. Implement strict local user privilege management to minimize the number of users with local access rights, reducing the attack surface. 4. Employ application whitelisting and endpoint detection and response (EDR) solutions to detect and block suspicious activities indicative of privilege escalation attempts. 5. Use Windows Defender Exploit Guard or similar technologies to harden memory protections and mitigate use-after-free exploitation techniques. 6. Restrict and monitor access to systems with legacy Windows versions, and plan for upgrading to supported Windows versions with ongoing security updates. 7. Conduct user awareness training to reduce the risk of initial local access through social engineering or phishing. 8. Enable detailed logging and monitoring of security events related to privilege escalation and notification subsystem activities to facilitate early detection.