CVE-2025-53716 is a vulnerability identified in Microsoft Windows 10 Version 1809 (build 10.0.17763.0) affecting the Local Security Authority Subsystem Service (LSASS). The issue is a NULL pointer dereference (CWE-476) that occurs when LSASS improperly handles certain network requests. An authorized attacker with network access and low privileges can exploit this flaw to cause a denial of service (DoS) by crashing the LSASS process, which is critical for enforcing security policies and managing authentication. The vulnerability has a CVSS v3.1 base score of 6.5, reflecting medium severity, with attack vector being network (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), no user interaction (UI:N), and impacting availability (A:H) only. Confidentiality and integrity are not affected. The flaw does not require user interaction and can be triggered remotely, but the attacker must have some level of authorization on the target system or network segment. No public exploits or active exploitation have been reported as of the publication date (August 12, 2025). The absence of patches at the time of reporting suggests organizations should prioritize mitigation through system upgrades or network segmentation. LSASS is a critical Windows component responsible for enforcing security policies, so its failure can cause system instability or forced reboots, leading to operational disruptions. This vulnerability primarily affects legacy Windows 10 installations, which may still be in use in some enterprise environments.

For European organizations, the primary impact of CVE-2025-53716 is the potential for denial of service attacks that disrupt authentication services and security policy enforcement on affected Windows 10 Version 1809 systems. This can lead to system instability, forced reboots, and interruption of critical business operations, especially in environments relying on legacy systems. While confidentiality and integrity are not compromised, availability degradation can affect user productivity and access to network resources. Organizations in sectors such as finance, healthcare, government, and critical infrastructure that still operate legacy Windows 10 systems may experience operational risks. Additionally, denial of service conditions on LSASS could complicate incident response and recovery efforts. The lack of known exploits reduces immediate risk, but the ease of exploitation and network accessibility mean attackers could weaponize this vulnerability if it becomes public. European entities with strict uptime and compliance requirements may face regulatory and reputational consequences if disruptions occur.

To mitigate CVE-2025-53716, European organizations should prioritize upgrading affected systems from Windows 10 Version 1809 to a supported and patched Windows version, as Microsoft has not yet released a patch for this vulnerability. In the interim, network segmentation should be enforced to restrict access to LSASS-related services, limiting exposure to authorized and trusted hosts only. Implementing strict access controls and monitoring network traffic for anomalous activity targeting LSASS can help detect exploitation attempts. Organizations should also review and minimize privileges for users and services that can interact with LSASS over the network to reduce the attack surface. Deploying endpoint detection and response (EDR) solutions capable of identifying LSASS crashes or abnormal behavior can aid in early detection. Regular backups and incident response plans should be updated to handle potential DoS scenarios. Finally, organizations must stay alert for Microsoft’s official patches or advisories and apply them promptly once available.