Intrusion Prevention

MS.Windows.NTLM.Message.MIC.Security.Policy.Bypass

Description

This indicates an attack attempt to exploit a Security Policy Bypass Vulnerability in Microsoft Windows Server.
A remote, man-in-the-middle attacker can exploit this vulnerability by tampering with the NTLM CHALLENGE and AUTHENTICATE messages. Successful exploitation results in the malicious modification of NTLM messages in order to provide the attacker with authenticated access to the target server.

Affected Products

Microsoft Windows 7
Microsoft Windows 8.1
Microsoft Windows 10
Microsoft Windows RT 8.1
Microsoft Windows Server 2008
Microsoft Windows Server 2008 R2
Microsoft Windows Server 2012
Microsoft Windows Server 2012 R2
Microsoft Windows Server 2016
Microsoft Windows Server 2019
Microsoft Windows Server version 1803 (Server Core Installation)
Microsoft Windows Server version 1903 (Server Core installation)

Impact

Privilege Escalation: Remote attackers can leverage their privileges on vulnerable systems

Recommended Actions

Apply the most recent upgrade or patch from the vendor.
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1166

CVE References

CVE-2019-1166