Open redirect in Microsoft Windows and Windows Server - CVE-2026-83646
Published: October 14, 2026
Vulnerability identifier: #VU154791
CSH Severity: Low
CVSS v4: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-83646
CWE-ID: CWE-601
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote privileged user to perform spoofing.
The vulnerability exists due to URL redirection to an untrusted site (open redirect) in Active Directory Federation Services (AD FS) when handling network-based redirections. A remote privileged user can redirect users to an untrusted site to perform spoofing.
User interaction is required.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-83646
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 1607 10.0.14393.9612, 10 1809 10.0.17763.9376
Windows Server - addressed in versions 2016 10.0.14393.9612, 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650
Windows Server - addressed in versions 2016 10.0.14393.9612, 2019 10.0.17763.9376, 2022 10.0.20348.5761, 2025 10.0.26100.33650