CVE-2024-21360 is a high-severity heap-based buffer overflow vulnerability (CWE-122) affecting Microsoft Windows 10 Version 1809, specifically version 10.0.17763.0. The flaw exists in the Windows Defender Application Control (WDAC) OLE DB provider for SQL Server, which is a component that facilitates database connectivity and operations. This vulnerability allows an unauthenticated remote attacker to execute arbitrary code on the affected system by exploiting the buffer overflow condition. The vulnerability is triggered remotely over the network (AV:N), requires no privileges (PR:N), but does require user interaction (UI:R), such as opening a malicious file or link. The scope is unchanged (S:U), meaning the exploit affects resources within the same security scope. The impact is critical across confidentiality, integrity, and availability (C:H/I:H/A:H), allowing full system compromise. The vulnerability has not yet been observed exploited in the wild, and no official patches have been linked at the time of this report. Given the nature of the vulnerability, successful exploitation could allow attackers to run arbitrary code with system privileges, potentially leading to data theft, system disruption, or deployment of further malware. The vulnerability was reserved in December 2023 and published in February 2024, indicating recent discovery and disclosure. The lack of a patch increases the urgency for mitigation and risk management, especially in environments where Windows 10 Version 1809 remains in use.

For European organizations, this vulnerability poses a significant risk, particularly for those still operating legacy systems like Windows 10 Version 1809, which may be common in industrial, governmental, or enterprise environments with slower upgrade cycles. Exploitation could lead to full system compromise, data breaches involving sensitive personal or corporate data, disruption of critical services, and potential lateral movement within networks. Sectors such as finance, healthcare, manufacturing, and public administration are especially vulnerable due to their reliance on SQL Server databases and Windows infrastructure. The high impact on confidentiality, integrity, and availability means that exploitation could result in severe operational and reputational damage, regulatory penalties under GDPR for data breaches, and financial losses. The requirement for user interaction suggests phishing or social engineering could be vectors, increasing the risk in environments with less mature cybersecurity awareness. The absence of known exploits in the wild currently reduces immediate threat but does not eliminate the risk of future exploitation, especially as threat actors often reverse-engineer disclosed vulnerabilities.

European organizations should prioritize the following mitigations: 1) Immediate inventory and identification of systems running Windows 10 Version 1809, particularly those utilizing the WDAC OLE DB provider for SQL Server. 2) Implement strict network segmentation and firewall rules to limit exposure of vulnerable systems to untrusted networks, reducing remote attack surface. 3) Enhance endpoint protection and monitoring to detect anomalous behaviors indicative of exploitation attempts, including unusual SQL Server activity or memory corruption indicators. 4) Conduct targeted user awareness training focusing on phishing and social engineering to mitigate the required user interaction vector. 5) Apply any available Microsoft security updates or workarounds as soon as they are released; monitor Microsoft advisories closely. 6) Consider upgrading affected systems to supported Windows versions with active security support to eliminate exposure. 7) Employ application whitelisting and restrict execution privileges for OLE DB provider components where feasible. 8) Regularly back up critical data and verify recovery procedures to minimize impact of potential ransomware or destructive attacks leveraging this vulnerability.