CVE-2025-53726 is a vulnerability classified under CWE-843 (Access of Resource Using Incompatible Type, commonly known as type confusion) affecting the Windows Push Notifications component in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw occurs when the system improperly handles resource access by using an incompatible data type, which can lead to memory corruption or unexpected behavior. An authorized local attacker can exploit this vulnerability to elevate their privileges on the affected system, potentially gaining administrative rights. The vulnerability does not require user interaction, making it easier to exploit once local access is obtained. The CVSS v3.1 base score is 7.8, reflecting high impact on confidentiality, integrity, and availability, with low attack complexity and requiring only limited privileges. No public exploits have been reported yet, but the vulnerability is publicly disclosed and considered critical for environments still running this older Windows version. The lack of available patches at the time of disclosure necessitates immediate attention to mitigate risk. This vulnerability highlights the risks associated with legacy operating system versions that may no longer receive regular security updates. Organizations relying on Windows 10 Version 1809 should prioritize upgrading to supported versions or apply any forthcoming patches promptly. Additionally, monitoring local user activities and restricting access to sensitive systems can reduce exploitation likelihood.

For European organizations, this vulnerability poses a significant risk, especially for those still operating Windows 10 Version 1809 in production or legacy environments. Successful exploitation allows local attackers to escalate privileges, potentially leading to full system compromise, unauthorized data access, and disruption of critical services. This can impact confidentiality by exposing sensitive information, integrity by allowing unauthorized modifications, and availability by enabling denial-of-service conditions through system instability or malicious actions. Sectors with high reliance on legacy Windows systems, such as manufacturing, healthcare, and government institutions, may face increased exposure. The vulnerability's local attack vector means that insider threats or attackers who gain initial foothold through other means (e.g., phishing) can leverage this flaw to deepen their access. Given Europe's stringent data protection regulations (e.g., GDPR), breaches resulting from such vulnerabilities can also lead to legal and financial repercussions. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits after public disclosure.

1. Upgrade affected systems from Windows 10 Version 1809 to a supported and fully patched Windows version to eliminate exposure to this vulnerability. 2. Until upgrades or patches are applied, restrict local access to critical systems by enforcing strict access controls and using least privilege principles. 3. Implement robust endpoint detection and response (EDR) solutions to monitor for unusual local privilege escalation attempts or suspicious activity related to Windows Push Notifications. 4. Harden system configurations by disabling or limiting Windows Push Notification services where feasible, especially on systems with sensitive data or critical functions. 5. Conduct regular audits of user accounts and permissions to identify and remove unnecessary local privileges that could be exploited. 6. Educate users and administrators about the risks of local privilege escalation and the importance of maintaining updated systems. 7. Prepare incident response plans specifically addressing potential exploitation scenarios involving local privilege escalation. 8. Monitor threat intelligence feeds for any emerging exploit code or attack campaigns targeting this CVE to enable rapid response.