CVE-2026-77484: Microsoft SQL Server Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

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

Less Likely

Patch Tuesday

2026-Sep

Released

2026-09-08

Description

Deserialization of untrusted data in SQL Server allows an authorized attacker to execute code over a network.

FAQ

How could an attacker exploit this vulnerability? An attacker could exploit this vulnerability by submitting a specially crafted payload to an affected service that deserializes untrusted data. Successful exploitation could allow the attacker to execute code on the target system.

Affected Products (6)

SQL Server

• Microsoft SQL Server 2019 for x64-based Systems (GDR)
• Microsoft SQL Server 2022 for x64-based Systems (GDR)
• Microsoft SQL Server 2025 for x64-based Systems (GDR)
• Microsoft SQL Server 2019 for x64-based Systems (CU 32)
• Microsoft SQL Server 2025 for x64-based Systems (CU8)
• Microsoft SQL Server 2022 for x64-based Systems (CU 26)

Security Updates (6)

• 5122773
• 5122771
• 5122770
• 5122772
• 5122769
• 5122768

Acknowledgments

<a href="https://twitter.com/chudypb">Piotr Bazydło (@chudypb)</a>

Revision History

• 2026-09-08: Information published.