CVE-2024-28926 is a high-severity heap-based buffer overflow vulnerability identified in Microsoft SQL Server 2022, specifically affecting the version 16.0.0 (CU 12). The vulnerability resides in the Microsoft OLE DB Driver for SQL Server, which is used to facilitate database connectivity and communication. A heap-based buffer overflow occurs when data exceeds the allocated buffer size on the heap, potentially allowing an attacker to overwrite adjacent memory. This can lead to arbitrary code execution, system crashes, or data corruption. In this case, the vulnerability enables remote code execution (RCE) without requiring prior authentication (PR:N), though it does require user interaction (UI:R), such as a user initiating a connection or query that triggers the flaw. The CVSS 3.1 base score is 8.8, indicating a high impact on confidentiality, integrity, and availability (all rated high). The attack vector is network-based (AV:N), meaning exploitation can occur remotely over the network, increasing the risk profile. The vulnerability scope is unchanged (S:U), meaning the impact is limited to the vulnerable component and does not extend beyond it. No known exploits are currently reported in the wild, but the presence of a critical memory corruption flaw in a widely deployed enterprise database product makes this a significant concern. The lack of available patches at the time of publication further elevates the urgency for mitigation. Given the role of SQL Server in critical business applications, exploitation could lead to full system compromise, data breaches, or disruption of business operations.

European organizations relying on Microsoft SQL Server 2022, particularly version 16.0.0 CU 12, face substantial risk from this vulnerability. SQL Server is widely used across sectors such as finance, manufacturing, healthcare, and government, all of which handle sensitive data and require high availability. Successful exploitation could lead to unauthorized data access, data manipulation, or complete system takeover, severely impacting confidentiality, integrity, and availability of critical business data. This could result in financial losses, regulatory penalties (especially under GDPR), reputational damage, and operational downtime. The remote exploitability without authentication means attackers can target exposed SQL Server instances directly over the network, increasing the attack surface. The requirement for user interaction may limit automated mass exploitation but does not significantly reduce risk in environments where users or automated systems interact with SQL Server regularly. The absence of known exploits currently provides a window for proactive defense, but the high severity score and nature of the vulnerability demand immediate attention to prevent potential future attacks.

1. Immediate deployment of any available security updates or patches from Microsoft once released is critical. Monitor official Microsoft security advisories closely for patch availability. 2. Until patches are available, restrict network access to SQL Server instances by implementing strict firewall rules limiting inbound connections to trusted IP addresses and networks only. 3. Disable or restrict the use of the Microsoft OLE DB Driver for SQL Server where possible, or configure it to minimize exposure, such as disabling unnecessary features or interfaces. 4. Employ network segmentation to isolate database servers from general user networks and the internet, reducing the likelihood of direct exploitation. 5. Monitor SQL Server logs and network traffic for unusual activity indicative of exploitation attempts, such as unexpected connection patterns or anomalous queries. 6. Enforce the principle of least privilege on SQL Server accounts and services to limit the potential impact of a successful exploit. 7. Educate users and administrators about the risk of this vulnerability and the importance of cautious interaction with database services. 8. Consider deploying intrusion detection/prevention systems (IDS/IPS) with updated signatures to detect attempts to exploit heap-based buffer overflows in SQL Server OLE DB Driver communications. 9. Regularly back up critical databases and verify backup integrity to enable rapid recovery in case of compromise.