CVE-2025-59209 is a vulnerability classified under CWE-200, indicating exposure of sensitive information to unauthorized actors. It affects Microsoft Windows 11 Version 25H2 (build 10.0.26200.0) specifically within the Windows Push Notification Core component. The vulnerability allows an attacker with authorized local access (low privileges) to disclose sensitive information without requiring user interaction. The attack vector is local, meaning the attacker must already have some level of access to the system, but does not require elevated privileges or user involvement. The vulnerability does not affect system integrity or availability but compromises confidentiality by leaking sensitive data that could be leveraged for further attacks or information gathering. The CVSS v3.1 base score is 5.5 (medium severity), with metrics indicating low attack complexity, low privileges required, no user interaction, and a confidentiality impact rated as high. No known exploits have been reported in the wild, and no patches have been officially released at the time of publication (October 14, 2025). The vulnerability was reserved on September 10, 2025, and published shortly thereafter. The lack of patch links suggests that mitigation currently relies on workarounds or access control measures. This vulnerability is significant for environments where local access cannot be tightly controlled or where sensitive information exposure could lead to compliance violations or targeted attacks.

For European organizations, the primary impact of CVE-2025-59209 is the unauthorized disclosure of sensitive information on Windows 11 Version 25H2 systems. This could lead to data leakage involving personal, financial, or intellectual property data, potentially violating GDPR and other data protection regulations. Confidentiality breaches may facilitate lateral movement or privilege escalation attempts by attackers with local access. Organizations in sectors such as finance, healthcare, government, and critical infrastructure are particularly at risk due to the sensitivity of their data and regulatory scrutiny. The vulnerability does not directly affect system availability or integrity, so operational disruption is unlikely. However, the exposure of sensitive information could undermine trust, lead to compliance penalties, and increase the risk of follow-on attacks. Since exploitation requires local access, the impact is mitigated somewhat by internal security controls, but insider threats or compromised endpoints remain a concern. European entities with remote or hybrid work environments should be vigilant about endpoint security to prevent unauthorized local access.

To mitigate CVE-2025-59209, European organizations should implement strict local access controls, ensuring that only trusted users have physical or remote desktop access to Windows 11 25H2 systems. Employ endpoint detection and response (EDR) solutions to monitor for unusual local activity indicative of exploitation attempts. Network segmentation can limit the spread of an attacker who gains local access. Since no official patch is currently available, organizations should apply any interim security advisories or workarounds provided by Microsoft promptly. Regularly audit and harden user privileges to minimize the number of accounts with local access rights. Employ encryption and data masking techniques to reduce the impact of any information disclosure. Prepare for rapid deployment of security updates once Microsoft releases a patch. Additionally, conduct user training to raise awareness about the risks of local access compromise and enforce strong authentication mechanisms for local logins. Finally, maintain comprehensive logging and incident response plans to detect and respond to potential exploitation.