CVE-2024-30011 is a security vulnerability identified in Microsoft Windows Server 2019, specifically affecting the Hyper-V virtualization component. The vulnerability is classified as an integer underflow (CWE-191), which occurs when an arithmetic operation causes a numeric value to wrap around below its minimum representable value, potentially leading to unexpected behavior. In this case, the flaw can be triggered remotely over the network (Attack Vector: Network) with low attack complexity and requires the attacker to have low privileges (PR:L) but no user interaction is needed. The vulnerability does not impact confidentiality or integrity but results in a denial of service (DoS) condition, causing the availability of the Hyper-V service or the host system to be disrupted. The CVSS v3.1 base score is 6.5, indicating a medium severity level. The scope is unchanged (S:U), meaning the vulnerability affects only the vulnerable component without impacting other system components. The vulnerability is currently not known to be exploited in the wild, and no patches have been publicly linked yet. The flaw arises from improper handling of integer values within Hyper-V, which could cause the service to crash or become unresponsive when processing specially crafted inputs, leading to service downtime or potential disruption of virtualized workloads hosted on Windows Server 2019 systems running version 10.0.17763.0.

For European organizations, the impact of this vulnerability primarily concerns availability disruptions in virtualized environments running Windows Server 2019 with Hyper-V enabled. Enterprises relying on Hyper-V for critical infrastructure, cloud services, or internal virtualization may experience service outages, affecting business continuity and operational efficiency. Since the vulnerability requires low privileges but no user interaction, insider threats or compromised low-privilege accounts could exploit it to cause denial of service. This could be particularly impactful for sectors with high virtualization dependency such as finance, telecommunications, government, and cloud service providers. Although no data confidentiality or integrity loss is indicated, the unavailability of virtual machines or services could lead to cascading operational issues, SLA violations, and potential financial losses. The absence of known exploits in the wild reduces immediate risk, but the medium severity score and ease of exploitation warrant timely mitigation to prevent potential future attacks.

Apply official Microsoft security updates as soon as they become available for Windows Server 2019, specifically targeting Hyper-V components. Implement strict access controls and monitoring on Hyper-V management interfaces to limit low-privilege account capabilities and detect anomalous activities. Use network segmentation and firewall rules to restrict access to Hyper-V hosts, minimizing exposure to untrusted networks. Regularly audit and harden virtualization hosts by disabling unnecessary services and features to reduce the attack surface. Establish robust incident response procedures to quickly identify and recover from potential denial of service incidents affecting virtualization infrastructure. Consider deploying Hyper-V hosts in high-availability clusters or with failover capabilities to mitigate service disruption impact. Monitor vendor advisories and threat intelligence feeds for updates on exploit developments or patches related to CVE-2024-30011.