CVE-2026-20932 is an information disclosure vulnerability classified under CWE-200 affecting Microsoft Windows 10 Version 1809 (build 17763.0). The vulnerability resides in Windows File Explorer, where an authorized local attacker with low privileges can access sensitive information without requiring user interaction. The attack vector is local (AV:L), with low attack complexity (AC:L), and requires privileges (PR:L) but no user interaction (UI:N). The vulnerability does not affect integrity or availability but has a high impact on confidentiality (C:H). The scope is unchanged (S:U), meaning the vulnerability affects resources within the same security scope. The CVSS v3.1 base score is 5.5, indicating medium severity. No known exploits have been reported in the wild, and no official patches have been linked yet, although the vulnerability has been publicly disclosed. The flaw could allow attackers to gather sensitive data that may facilitate further attacks or violate privacy policies. Since Windows 10 Version 1809 is an older release, many organizations may have migrated to newer versions; however, legacy systems remain at risk. The vulnerability highlights the importance of controlling local access and monitoring for unauthorized data access attempts within enterprise environments.

For European organizations, the exposure of sensitive information through this vulnerability could lead to unauthorized disclosure of confidential data, potentially including personal data protected under GDPR. This could result in privacy violations, regulatory penalties, and reputational damage. The vulnerability does not allow remote exploitation, limiting its impact to insiders or attackers who have already gained local access, such as through compromised credentials or physical access. However, in sectors with high security requirements—such as finance, healthcare, and critical infrastructure—the leakage of sensitive information could facilitate lateral movement or privilege escalation by adversaries. Organizations relying on legacy Windows 10 1809 systems are particularly vulnerable. The impact is mitigated if organizations have strict local access controls and monitoring in place. Nonetheless, failure to address this vulnerability could increase the risk profile of affected systems and complicate compliance with European data protection regulations.

European organizations should first identify and inventory all systems running Windows 10 Version 1809 (build 17763.0) to assess exposure. Since no official patch is currently linked, organizations should implement strict local access controls, ensuring only trusted users have physical or remote local access to affected systems. Employing endpoint detection and response (EDR) solutions to monitor for unusual file access patterns in Windows File Explorer can help detect exploitation attempts. Restricting the use of File Explorer or sensitive file access through application control policies or sandboxing may reduce risk. Organizations should also consider upgrading affected systems to a supported and patched Windows version to eliminate the vulnerability. Regularly reviewing user privileges and enforcing the principle of least privilege will limit the potential for exploitation. Finally, preparing for patch deployment by monitoring Microsoft advisories and testing patches in controlled environments will enable rapid remediation once updates are available.