Heap-based buffer overflow in Microsoft Windows and Windows Server - CVE-2026-49164

Vulnerability identifier: #VU137928

CSH Severity: High

CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-49164

CWE-ID: CWE-122

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to execute arbitrary code.

The vulnerability exists due to heap-based buffer overflow in Active Directory Domain Services when handling network requests. A remote attacker can send specially crafted requests to execute arbitrary code.

Successful exploitation requires additional actions to prepare the target environment.

Microsoft Windows
Windows Server

Install security update from vendor's website.

Microsoft Windows - addressed in versions 10 21H2 10.0.19044.7548, 10 22H2 10.0.19045.7548, 10 1607 10.0.14393.9339, 10 1809 10.0.17763.9020, 11 24H2 10.0.26100.8875, 11 25H2 10.0.26200.8875, 11 26H1 10.0.28000.2269, 11 26H1 10.0.28000.2525
Windows Server - addressed in versions 2012 R2 6.3.9600.23291, 2012 6.2.9200.26226, 2016 10.0.14393.9339, 2019 10.0.17763.9020, 2022 10.0.20348.5386, 2025 10.0.26100.33158

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2026-49164

• Multiple vulnerabilities in Microsoft Windows