CVE-2026-67643: Microsoft SQL Server Remote Code Execution Vulnerability

Overview

Severity

Critical (CVSS 9.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Category

Remote Code Execution

Exploit Status

Not Exploited

Exploitation Likelihood

Unlikely

Patch Tuesday

2026-Sep

Released

2026-09-08

Last Updated

2026-09-17

EPSS Score

0.97% (percentile: 61.7%)

Description

Heap-based buffer overflow in SQL Server allows an unauthorized attacker to execute code over a network.

Affected Products (4)

SQL Server

• Microsoft SQL Server 2022 for x64-based Systems (GDR)
• Microsoft SQL Server 2025 for x64-based Systems (GDR)
• Microsoft SQL Server 2022 for x64-based Systems (CU 26)
• Microsoft SQL Server 2025 for x64-based Systems (CU8)

Security Updates (4)

• 5122771
• 5122770
• 5122768
• 5122769

Acknowledgments

Microsoft Red Team

Revision History

• 2026-09-08: Information published.
• 2026-09-16: The CVSS vector string was update to reflect that an attacker does not require any privileges to successfully exploit this vulnerability (PR:N). This is an informational change only.
• 2026-09-17: The FAQs have been updated for this CVE