CVE-2026-61920: Windows DNS Server Remote Code Execution Vulnerability

Overview

Severity

Medium (CVSS 6.6)

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:H/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-Aug

Released

2026-08-11

Last Updated

2026-09-08

EPSS Score

0.52% (percentile: 41.7%)

Description

Concurrent execution using shared resource with improper synchronization ('race condition') in Windows DNS allows an authorized attacker to execute code over a network.

FAQ

According to the CVSS metric, the attack complexity is high (AC:H). What does that mean for this vulnerability? Successful exploitation of this vulnerability requires an attacker to win a race condition.

Affected Products (10)

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
• Windows Server 2016
• Windows Server 2016 (Server Core installation)

ESU

• Windows Server 2012 R2
• Windows Server 2012 R2 (Server Core installation)

Security Updates (7)

• 5120238
• 5120242
• 5120229
• 5120233
• 5120228
• 5120418
• 5120385

Acknowledgments

k0shl

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.