CVE-2026-77486: Microsoft SQL Server Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/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

Description

Integer overflow or wraparound in SQL Server allows an unauthorized attacker to execute code over a network.

FAQ

How could an attacker exploit this vulnerability? An attacker could host a malicious server and convince a user to connect to it from an affected client. When the client processes the server's response, the attacker could execute code on the client system. User interaction is required.

Affected Products (4)

SQL Server

• Microsoft SQL Server 2017 for x64-based Systems (GDR)
• Microsoft SQL Server 2019 for x64-based Systems (GDR)
• Microsoft SQL Server 2017 for x64-based Systems (CU 31)
• Microsoft SQL Server 2019 for x64-based Systems (CU 32)

Security Updates (4)

• 5122775
• 5122773
• 5122774
• 5122772

Acknowledgments

yhw & txz

Revision History

• 2026-09-08: Information published.