Improper authentication in Windows and Windows Server - CVE-2017-8563

 

Improper authentication in Windows and Windows Server - CVE-2017-8563

Published: July 11, 2017 / Updated: July 11, 2017


Vulnerability identifier: #VU7453
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2017-8563
CWE-ID: CWE-287
Exploitation vector: Adjecent network
Exploit availability: No public exploit available
Vendor: Microsoft
Affected software:
Windows
Windows Server

Detailed vulnerability description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists in Microsoft Windows when Kerberos falls back to NT LAN Manager (NTLM) Authentication Protocol as the default authentication protocol. A remote attacker can send specially crafted requests to domain controller and trigger the fall back to less secure authentication protocol.

Successful exploitation of the vulnerability may allow an attacker to perform a MitM attack, intercept network traffic and gain access to users’ credentials.


How to mitigate CVE-2017-8563

Install updates from vendor's website.

Note: To make LDAP authentication over SSL/TLS more secure, administrators need to create a LdapEnforceChannelBinding registry setting on a Domain Controller. For more information about setting this registry key, see Microsoft Knowledge Base article 4034879.

Sources