Seraphim Digital Technology

Microsoft has released security updates to fix a serious vulnerability in SQL Server that allows attackers to gain higher system privileges.

The flaw, tracked as CVE-2025-59499, was disclosed on November 11, 2025, and affects multiple versions including SQL Server 2016, 2017, 2019, and 2022.

This vulnerability stems from improper handling of special characters in SQL commands, creating an opening for SQL injection attacks that can compromise database security.

The vulnerability carries a CVSS score of 8.8, marking it as a high-severity issue that requires immediate attention from system administrators.

An attacker with low-level access can exploit this flaw over a network without any user interaction, making it particularly dangerous for exposed database servers.

The issue affects the confidentiality, integrity, and availability of SQL Server systems, potentially allowing unauthorized access to sensitive data and system controls.

Microsoft security researchers identified this vulnerability as a SQL injection weakness classified under CWE-89.

The flaw allows authorized users with limited privileges to inject malicious T-SQL commands through specially crafted database names.

When successfully exploited, attackers can execute arbitrary commands with elevated permissions, potentially gaining complete control over the database system.

Attack Mechanism

The vulnerability works by exploiting how SQL Server processes database names in queries. Attackers can craft malicious database names containing special SQL characters that are not properly sanitized by the server.

When these crafted names are processed, the injected T-SQL commands execute with the privileges of the process running the query.

If the process runs with sysadmin privileges, the attacker gains full administrative control over the entire SQL Server instance, allowing them to read, modify, or delete any data, create new accounts, or execute system-level commands.

Microsoft has released security patches for all affected versions through both General Distribution Release (GDR) and Cumulative Update (CU) channels.

Administrators should immediately apply the appropriate updates based on their current SQL Server version and update path to protect their systems from potential exploitation.