CVE-2026-49181: Windows DHCP Client Elevation of Privilege Vulnerability

Overview

Severity

High (CVSS 7.5)

CVSS Vector

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

Category

Elevation of Privilege

Exploit Status

Not Exploited

Exploitation Likelihood

Less Likely

Patch Tuesday

2026-Jul

Released

2026-07-14

Description

Integer underflow (wrap or wraparound) in Windows DHCP Client allows an unauthorized attacker to elevate privileges over a network.

FAQ

What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.

Affected Products (15)

Windows

• Windows 10 Version 1809 for 32-bit Systems
• Windows 10 Version 1809 for x64-based Systems
• Windows Server 2019
• Windows Server 2019 (Server Core installation)
• Windows Server 2022
• Windows Server 2025 (Server Core installation)
• Windows Server 2025
• Windows 10 Version 1607 for 32-bit Systems
• Windows 10 Version 1607 for x64-based Systems
• Windows Server 2016
• Windows Server 2016 (Server Core installation)

ESU

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

Security Updates (6)

• 5099538
• 5099540
• 5099536
• 5099535
• 5099445
• 5099444

Acknowledgments

Jay Ladhad with Microsoft

Revision History

• 2026-07-14: Information published.