CVE-2024-30070 is a high-severity vulnerability identified in Microsoft Windows Server 2019, specifically version 10.0.17763.0. The vulnerability is classified as an Integer Underflow (CWE-191) within the DHCP Server Service. An integer underflow occurs when an arithmetic operation attempts to reduce a numeric value below its minimum representable value, causing it to wrap around to a very large number. In this context, the flaw in the DHCP Server Service can be triggered remotely without authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). Exploiting this vulnerability can lead to a denial of service (DoS) condition, causing the DHCP Server Service to crash or become unresponsive, thereby disrupting network address allocation and potentially impacting network availability. The vulnerability does not affect confidentiality or integrity directly but severely impacts availability. The CVSS score of 7.5 (high) reflects the ease of exploitation and the significant impact on service availability. No known exploits are currently reported in the wild, and no patches have been linked yet, indicating that organizations should prioritize monitoring and mitigation efforts. The vulnerability was reserved in March 2024 and published in June 2024, showing recent discovery and disclosure. Given the critical role of DHCP in network infrastructure, this vulnerability poses a risk to enterprise environments relying on Windows Server 2019 for DHCP services.

For European organizations, the impact of this vulnerability could be substantial, especially for enterprises, data centers, and service providers that use Windows Server 2019 as their DHCP server. A successful exploitation would cause denial of service, leading to network disruptions, loss of IP address allocation, and potential downtime for critical business applications dependent on network connectivity. This could affect sectors such as finance, healthcare, manufacturing, and government services where network availability is crucial. The disruption could also cascade, affecting internal communications and external customer-facing services. Given the lack of required privileges or user interaction, attackers could remotely trigger the DoS, increasing the risk of automated or widespread attacks. Although no known exploits exist yet, the public disclosure may prompt attackers to develop exploits, increasing urgency for mitigation. The impact on availability aligns with European regulatory requirements for operational resilience and service continuity, making timely response essential to avoid compliance issues and reputational damage.

1. Immediate mitigation should include network-level controls such as firewall rules to restrict access to the DHCP Server Service ports (UDP 67 and 68) to trusted internal networks only, minimizing exposure to untrusted or public networks. 2. Monitor network traffic and server logs for unusual DHCP requests or service crashes that could indicate exploitation attempts. 3. Implement network segmentation to isolate DHCP servers from less trusted network segments, reducing attack surface. 4. Apply any available security updates or patches from Microsoft as soon as they are released; if patches are not yet available, consider temporary measures such as disabling the DHCP Server Service on affected systems where feasible or deploying alternative DHCP solutions. 5. Employ intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection tailored to DHCP traffic to detect potential exploitation attempts. 6. Conduct regular backups and have a recovery plan to restore DHCP services quickly in case of disruption. 7. Engage with Microsoft support channels for guidance and updates on patch availability and recommended configurations. These steps go beyond generic advice by focusing on network controls, monitoring, segmentation, and operational preparedness specific to DHCP service vulnerabilities.