A heap-based buffer overflow in Microsoft SQL Server permits an attacker with authorized access to elevate privileges locally. The underlying weakness is identified as a buffer overflow that can corrupt executable memory and change control flow, allowing the attacker to run code with higher permissions than originally granted. The impact therefore is that a local user could gain administrative rights on the affected server, compromising integrity and potentially enabling further attacks.

Microsoft products affected are SQL Server 2017 (GDR), SQL Server 2017 for x64-based Systems (CU31), SQL Server 2019 (GDR), SQL Server 2019 for x64-based Systems (CU32), SQL Server 2022 (GDR), SQL Server 2022 for x64-based Systems (CU27), SQL Server 2025 (CU8), SQL Server 2025 for x64-based Systems (CU9), and SQL Server 2025 for x64-based Systems (GDR).

The CVSS score of 6.4 classifies the flaw as a medium severity vulnerability. With an EPSS score of less than 1%, the likelihood of exploitation at this time is low, and the vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog. The vulnerability requires an attacker to have local or authorized access to the SQL Server instance, after which the heap corruption can be triggered to execute higher‑privilege code. No publicly disclosed exploits are referenced in the advisory.