CVE-2025-53804 is a medium-severity vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0). It involves an exposure of sensitive information due to a flaw in the Windows Kernel, which allows an authorized local attacker to disclose sensitive information without requiring user interaction. The vulnerability is classified under CWE-200, indicating an exposure of sensitive information to an unauthorized actor. The CVSS 3.1 base score is 5.5, reflecting a moderate risk level. The attack vector is local (AV:L), meaning the attacker must have local access to the affected system. The attack complexity is low (AC:L), and privileges required are low (PR:L), so an attacker with limited privileges can exploit this issue. No user interaction is needed (UI:N), and the scope is unchanged (S:U). The impact is high on confidentiality (C:H), but there is no impact on integrity (I:N) or availability (A:N). The vulnerability does not currently have any known exploits in the wild, and no patches or mitigation links have been published yet. The flaw allows an attacker with local access to the system to gain access to sensitive kernel information that should otherwise be protected, potentially aiding further attacks or information gathering. Since it affects Windows 10 Version 1809, which is an older version of Windows 10, systems still running this version are at risk. The vulnerability is significant because kernel-level information disclosure can be leveraged to bypass security controls or escalate privileges in chained attacks.

For European organizations, this vulnerability poses a risk primarily to endpoints and servers still running Windows 10 Version 1809, which may be present in legacy environments or systems not yet upgraded. Exposure of sensitive kernel information can facilitate further attacks such as privilege escalation or bypassing security mechanisms, potentially leading to data breaches or system compromise. Confidentiality of sensitive data could be compromised, especially in sectors handling critical or regulated information such as finance, healthcare, and government. Although the vulnerability requires local access and low privileges, insider threats or attackers who have gained initial footholds could exploit this to deepen their access. The lack of user interaction needed increases the risk in automated or unattended environments. The absence of known exploits in the wild reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once the vulnerability details become widely known. Organizations relying on Windows 10 Version 1809 should consider this vulnerability in their risk assessments and prioritize remediation or mitigation to protect sensitive information and maintain compliance with data protection regulations such as GDPR.

1. Upgrade affected systems from Windows 10 Version 1809 to a supported and fully patched version of Windows 10 or Windows 11 to eliminate exposure to this vulnerability. 2. Until upgrades are possible, restrict local access to systems running the vulnerable version by enforcing strict physical security and limiting user accounts with local login privileges. 3. Implement application whitelisting and endpoint detection and response (EDR) solutions to monitor and block suspicious local activities that could attempt to exploit kernel information disclosure. 4. Use least privilege principles to ensure users and processes operate with minimal necessary permissions, reducing the risk that low-privilege accounts can exploit this vulnerability. 5. Monitor system logs and audit local access events to detect unusual or unauthorized access attempts. 6. Stay informed on Microsoft security advisories for any forthcoming patches or mitigations related to CVE-2025-53804 and apply them promptly once available. 7. Conduct regular vulnerability assessments and penetration testing focusing on legacy systems to identify and remediate similar risks proactively.