Weak Authentication in Microsoft Windows and Windows Server - CVE-2026-73025
Published: September 9, 2026
Vulnerability identifier: #VU148169
CSH Severity: High
CVSS v4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-73025
CWE-ID: CWE-1390
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to access mapped storage without CHAP authentication.
The vulnerability exists due to weak authentication in Windows iSCSI when processing specially crafted authentication data sent to an affected iSCSI Target Server. A remote attacker can send specially crafted authentication data to access mapped storage without CHAP authentication.
User interaction is not required.
Affected software
Microsoft Windows
Windows Server
Windows Server
How to mitigate CVE-2026-73025
Install security update from vendor's website.
Microsoft Windows - addressed in versions 10 1607 10.0.14393.9512, 10 1809 10.0.17763.9245
Windows Server - addressed in versions 2012 R2 6.3.9600.23397, 2012 6.2.9200.26349, 2016 10.0.14393.9512, 2019 10.0.17763.9245, 2022 10.0.20348.5622, 2025 10.0.26100.33438
Windows Server - addressed in versions 2012 R2 6.3.9600.23397, 2012 6.2.9200.26349, 2016 10.0.14393.9512, 2019 10.0.17763.9245, 2022 10.0.20348.5622, 2025 10.0.26100.33438