CVE-2026-62817: Windows DNS Server Remote Code Execution Vulnerability

Overview

Severity

High (CVSS 8.8)

CVSS Vector

CVSS:3.1/AV:A/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

Less Likely

Patch Tuesday

2026-Aug

Released

2026-08-11

Last Updated

2026-09-08

EPSS Score

0.53% (percentile: 42.7%)

Description

Out-of-bounds write in Windows DNS allows an unauthorized attacker to execute code over an adjacent network.

FAQ

How could an attacker exploit this vulnerability? Successful exploitation of this vulnerability could allow an attacker the ability to gain remote code execution via an in-network attacker calling arbitrary endpoints.

Affected Products (6)

Windows

• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2022 (Server Core installation)
• Windows Server 2025 (Server Core installation)
• Windows Server 2025

Security Updates (5)

• 5120238
• 5120242
• 5120229
• 5120233
• 5120228

Revision History

• 2026-08-11: Information published.
• 2026-09-08: Updated software table to remove clients versions because this vulnerability only impacts Windows Servers. This is an informational change only.