CVE-2025-53805 is a high-severity vulnerability identified as an out-of-bounds read (CWE-125) in Microsoft Windows Server 2022, specifically within the Windows Internet Information Services (IIS) component. This vulnerability allows an unauthorized attacker to perform a denial-of-service (DoS) attack over the network without requiring any authentication or user interaction. The flaw arises from improper bounds checking in IIS, which leads to reading memory outside the intended buffer boundaries. While this does not directly compromise confidentiality or integrity, the out-of-bounds read can cause the IIS service or the entire Windows Server 2022 system to crash or become unresponsive, resulting in service disruption. The CVSS v3.1 base score is 7.5, reflecting a high severity due to the network attack vector, low attack complexity, and no privileges or user interaction needed. No known exploits have been reported in the wild yet, and no patches or mitigations have been officially released at the time of publication. The vulnerability affects Windows Server 2022 version 10.0.20348.0, which is widely used in enterprise environments for hosting web applications and services. Given the critical role of IIS in web hosting and the importance of Windows Server 2022 in modern data centers, this vulnerability poses a significant risk of service outages if exploited.

For European organizations, the impact of CVE-2025-53805 can be substantial, especially for those relying on Windows Server 2022 to host critical web services, intranet portals, or cloud-based applications. A successful exploitation would result in denial of service, causing downtime and potential disruption of business operations, customer-facing services, and internal workflows. This could lead to financial losses, reputational damage, and compliance issues, particularly under regulations like GDPR that mandate availability and resilience of IT services. Sectors such as finance, healthcare, government, and telecommunications, which heavily depend on IIS for secure and reliable web hosting, are at heightened risk. Additionally, the lack of authentication or user interaction requirements lowers the barrier for attackers, increasing the likelihood of opportunistic or targeted DoS attacks. Although no data breach or code execution is indicated, the availability impact alone can be critical for service continuity in European enterprises.

European organizations should prioritize the following mitigation steps: 1) Immediate inventory and identification of all Windows Server 2022 instances running IIS version 10.0.20348.0 to assess exposure. 2) Monitor official Microsoft security advisories closely for the release of patches or security updates addressing CVE-2025-53805 and apply them promptly once available. 3) Implement network-level protections such as Web Application Firewalls (WAFs) and Intrusion Prevention Systems (IPS) configured to detect and block anomalous or malformed HTTP requests that could trigger the out-of-bounds read. 4) Employ rate limiting and connection throttling on IIS to reduce the impact of potential DoS attempts. 5) Segment IIS servers from critical infrastructure and restrict access to trusted networks to minimize exposure. 6) Maintain robust monitoring and alerting on IIS service health and network traffic patterns to detect early signs of exploitation attempts. 7) Consider temporary mitigation by disabling or restricting vulnerable IIS features if feasible until patches are deployed. These targeted actions go beyond generic advice by focusing on proactive detection, containment, and rapid patch management tailored to this specific vulnerability.