STIGQter: STIG Summary: Microsoft Exchange 2016 Mailbox Server Security Technical Implementation Guide Version: 2 Release: 3 Benchmark Date: 23 Apr 2021:

Exchange Outlook Anywhere clients must use NTLM authentication to access email.

DISA Rule

SV-228404r612748_rule

Vulnerability Number

V-228404

Group Title

SRG-APP-000391

Rule Version

EX16-MB-000610

Severity

CAT II

CCI(s)

• CCI-001953 - The information system accepts Personal Identity Verification (PIV) credentials.

Weight

10

Fix Recommendation

Open the Exchange Management Shell and enter the following command:

For InternalClientAuthenticationMethod:

Set-OutlookAnywhere -Identity '<IdentityName'> -InternalClientAuthenticationMethod NTLM

For ExternalClientAuthenticationMethod:

Set-OutlookAnywhere -Identity '<IdentityName'> -ExternalClientAuthenticationMethod NTLM

Check Contents

Open the Exchange Management Shell and enter the following command:

Get-OutlookAnywhere

Get-OutlookAnywhere | Select Name, Identity, InternalClientAuthenticationMethod, ExternalClientAuthenticationMethod

If the value of "InternalClientAuthenticationMethod" and the value of "ExternalClientAuthenticationMethod" are not set to NTLM, this is a finding.

Vulnerability Number

V-228404

Documentable

False

Rule Version

EX16-MB-000610

Severity Override Guidance

Open the Exchange Management Shell and enter the following command:

Get-OutlookAnywhere

Get-OutlookAnywhere | Select Name, Identity, InternalClientAuthenticationMethod, ExternalClientAuthenticationMethod

If the value of "InternalClientAuthenticationMethod" and the value of "ExternalClientAuthenticationMethod" are not set to NTLM, this is a finding.

Check Content Reference

M

Target Key

4223

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