CVE-2025-53726 is a high-severity vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0) that involves a type confusion flaw (CWE-843) within the Windows Push Notifications component. Type confusion vulnerabilities occur when a program accesses a resource or memory using an incorrect or incompatible data type, potentially leading to unexpected behavior or memory corruption. In this specific case, the vulnerability allows an authorized local attacker to exploit the Windows Push Notifications system to elevate their privileges on the affected machine. The attacker must already have some level of local access (low privileges) but does not require user interaction to exploit the flaw. The vulnerability impacts confidentiality, integrity, and availability, as indicated by the CVSS vector (C:H/I:H/A:H). The CVSS score of 7.8 reflects a high-risk vulnerability due to the combination of local attack vector, low attack complexity, and the ability to fully compromise the system by escalating privileges. No known exploits are currently reported in the wild, and no patches or mitigation links have been provided at the time of publication (August 12, 2025). This vulnerability is particularly concerning because Windows Push Notifications are a core system component used for delivering notifications and messages, and exploitation could allow attackers to bypass security controls and gain SYSTEM-level privileges, potentially leading to full system compromise or lateral movement within a network.

For European organizations, this vulnerability poses a significant risk, especially in environments where Windows 10 Version 1809 is still in use, such as legacy systems or specialized industrial control systems that have not been updated. Successful exploitation could allow attackers to escalate privileges from a low-privileged user account to SYSTEM level, enabling them to install malware, exfiltrate sensitive data, disrupt services, or move laterally within corporate networks. This could impact confidentiality by exposing sensitive corporate or personal data, integrity by allowing unauthorized changes to system configurations or files, and availability by enabling denial-of-service conditions or ransomware deployment. Given the local attack vector, insider threats or attackers who have gained initial footholds via phishing or other means could leverage this vulnerability to deepen their access. The lack of user interaction requirement increases the risk of automated or stealthy exploitation once local access is obtained. European organizations in critical infrastructure sectors, finance, healthcare, and government are particularly at risk due to the potential impact on sensitive data and operational continuity.

1. Immediate patching: Although no official patch links are provided yet, organizations should monitor Microsoft’s security advisories closely and apply patches as soon as they become available. 2. Upgrade Windows versions: Where feasible, upgrade systems from Windows 10 Version 1809 to a more recent, supported Windows version that does not contain this vulnerability. 3. Restrict local access: Limit the number of users with local access rights, enforce the principle of least privilege, and use endpoint protection solutions to detect and prevent unauthorized local access attempts. 4. Application whitelisting and behavior monitoring: Deploy application control to prevent unauthorized code execution and monitor for suspicious activities related to Windows Push Notifications or privilege escalation attempts. 5. Network segmentation: Isolate legacy systems running vulnerable Windows versions to reduce the risk of lateral movement if compromised. 6. Incident response readiness: Prepare detection rules and response playbooks for privilege escalation attempts, including monitoring for anomalous use of Windows Push Notifications APIs or related system calls. 7. User education: Train users to recognize and report suspicious activity that could lead to local compromise, such as phishing or social engineering attacks that may precede exploitation.