CVE-2024-28939 is a high-severity vulnerability affecting Microsoft SQL Server 2019 (CU 25), specifically related to the Microsoft OLE DB Driver for SQL Server. The vulnerability is categorized under CWE-209, which involves the generation of error messages containing sensitive information. This flaw allows an unauthenticated remote attacker to potentially execute remote code on the affected system. The CVSS 3.1 base score of 8.8 reflects the critical nature of this vulnerability, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requiring user interaction (UI:R). The scope is unchanged (S:U), and the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). The vulnerability arises because the OLE DB Driver improperly handles error messages, potentially leaking sensitive internal information that can be leveraged by attackers to craft further exploits, including remote code execution. Although no known exploits are currently observed in the wild, the vulnerability's characteristics suggest that exploitation could lead to full system compromise. The lack of available patches at the time of publication increases the urgency for mitigation and monitoring. The vulnerability was reserved in March 2024 and published in April 2024, indicating recent discovery and disclosure.

For European organizations, this vulnerability poses a significant risk due to the widespread use of Microsoft SQL Server 2019 in enterprise environments, including finance, healthcare, manufacturing, and government sectors. Exploitation could lead to unauthorized access, data breaches involving sensitive personal and corporate data, disruption of critical business operations, and potential ransomware deployment. The high impact on confidentiality, integrity, and availability means that attackers could not only exfiltrate data but also alter or destroy it, severely affecting trust and compliance with regulations such as GDPR. The requirement for user interaction slightly reduces the risk of automated mass exploitation but does not eliminate targeted attacks, especially spear-phishing or social engineering campaigns aimed at privileged users or database administrators. The absence of known exploits in the wild currently provides a window for proactive defense, but the vulnerability’s severity demands immediate attention to prevent potential future attacks.

1. Immediate deployment of any available security updates or patches from Microsoft as they become available is critical. Since no patches were linked at the time of disclosure, organizations should monitor Microsoft’s security advisories closely. 2. Implement strict network segmentation and firewall rules to limit access to SQL Server instances, especially restricting OLE DB Driver usage to trusted hosts and networks. 3. Employ application-layer filtering and intrusion detection/prevention systems (IDS/IPS) to detect anomalous queries or error message patterns that may indicate exploitation attempts. 4. Enforce the principle of least privilege for database users and service accounts to minimize the impact of a successful exploit. 5. Educate users and administrators about the risks of social engineering and the importance of cautious interaction with unexpected prompts or error messages. 6. Enable detailed logging and continuous monitoring of SQL Server error messages and access logs to identify suspicious activities early. 7. Consider temporary disabling or restricting the use of the OLE DB Driver for SQL Server if feasible within operational constraints until patches are applied. 8. Conduct regular vulnerability assessments and penetration testing focusing on SQL Server environments to identify and remediate related weaknesses.