CVE-2025-29954 is a vulnerability classified under CWE-400 (Uncontrolled Resource Consumption) affecting Microsoft Windows 10 Version 1809 (build 10.0.17763.0). The flaw resides in the implementation of the Lightweight Directory Access Protocol (LDAP) service on the affected Windows version. Specifically, the vulnerability allows an unauthorized attacker to send specially crafted network requests to the LDAP service, causing excessive consumption of system resources such as CPU, memory, or network bandwidth. This resource exhaustion can lead to a denial of service (DoS) condition, rendering the LDAP service and potentially the entire system unresponsive or significantly degraded in performance. The vulnerability does not require any authentication or user interaction, and can be exploited remotely over the network. However, the attack complexity is rated as high, indicating that exploitation may require specific conditions or expertise. The CVSS v3.1 base score is 5.9 (medium severity), reflecting the lack of impact on confidentiality or integrity, but a significant impact on availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The LDAP service is critical in enterprise environments for directory services, authentication, and authorization, making this vulnerability particularly relevant for organizations relying on Windows 10 Version 1809 in their infrastructure.

For European organizations, this vulnerability poses a risk primarily to availability of directory services that underpin identity management and access control. Disruption of LDAP services can halt authentication processes, impede access to network resources, and affect dependent applications and services. This can lead to operational downtime, productivity loss, and potential cascading failures in IT environments. Organizations in sectors such as finance, healthcare, government, and critical infrastructure, which heavily rely on Windows-based directory services, may experience significant operational impact. Additionally, since the vulnerability can be exploited remotely without authentication, it increases the attack surface for threat actors aiming to disrupt services. Although the vulnerability does not compromise data confidentiality or integrity, the denial of service could be leveraged as part of multi-stage attacks or to distract security teams during other malicious activities.

Given the absence of an official patch, European organizations should implement the following specific mitigations: 1) Restrict network access to LDAP services by enforcing strict firewall rules and network segmentation, allowing only trusted hosts and management stations to communicate with LDAP servers. 2) Monitor LDAP traffic for abnormal patterns indicative of resource exhaustion attempts, using intrusion detection/prevention systems (IDS/IPS) and network behavior anomaly detection tools. 3) Apply rate limiting or connection throttling on LDAP endpoints where possible to mitigate excessive request floods. 4) Upgrade affected systems to a later Windows 10 version or Windows Server version where this vulnerability is addressed, as Windows 10 Version 1809 is an older release with limited support. 5) Employ robust logging and alerting on LDAP service performance metrics to detect early signs of exploitation attempts. 6) Develop and test incident response plans specifically for LDAP service disruptions to minimize downtime. These targeted controls go beyond generic advice by focusing on network-level restrictions, monitoring, and system upgrades tailored to the LDAP service and the affected Windows version.