STIGViewer Support

The Exchange client authentication with Exchange servers must be enabled to use Kerberos Password Authentication.

Overview

Finding IDVersionRule IDIA ControlsSeverity
V-223346O365-OU-000001SV-223346r961878_ruleCCI-001967medium
Description
This policy setting controls which authentication method Outlook uses to authenticate with Microsoft Exchange Server. Note: Exchange Server supports the Kerberos authentication protocol and NTLM for authentication. The Kerberos protocol is the more secure authentication method and is supported on Windows 2000 Server and later versions. NTLM authentication is supported in pre-Windows 2000 environments. If you enable this policy setting, you can choose from three different options for controlling how Outlook authenticates with Microsoft Exchange Server: - Kerberos/NTLM password authentication. Outlook attempts to authenticate using the Kerberos authentication protocol. If this attempt fails, Outlook attempts to authenticate using NTLM. This option is the default configuration. - Kerberos password authentication. Outlook attempts to authenticate using the Kerberos protocol only. - NTLM password authentication. Outlook attempts to authenticate using NTLM only. If you disable or do not configure this policy setting, Outlook will attempt to authenticate using the Kerberos authentication protocol. If it cannot (because no Windows 2000 or later domain controllers are available), it will authenticate using NTLM.
STIGDate
Microsoft Office 365 ProPlus Security Technical Implementation Guide2026-02-12

Related Frameworks

1 mapping across 4 frameworks
SCF0 mappings

No source states a mapping between these directly.

Also reachable in 3 hops (1) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

IAC-04Identification & Authentication for Devices
0.50
NIST 800-530 mappings

No source states a mapping between these directly.

Also reachable in 2 hops (49) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

AC-17(10)Authenticate Remote Commands
1.00
AC-17(2)Protection of Confidentiality and Integrity Using Encryption
1.00
AC-18(1)Authentication and Encryption
1.00
AC-2(1)Automated System Account Management
1.00
AC-2(11)Usage Conditions
1.00
AC-2(2)Automated Temporary and Emergency Account Management
1.00
AC-2(3)Disable Accounts
1.00
AC-4(17)Domain Authentication
1.00
AC-7Unsuccessful Logon Attempts
1.00
AU-8Time Stamps
1.00

+39 more (top 10 by confidence shown)

CCI1 mapping
NIST CSF 2.00 mappings

No source states a mapping between these directly.

Also reachable in 4 hops (3) derived by us, not asserted by any source

Each of these is a route we composed by chaining published mappings. No publisher states a relationship between the two endpoints.

Details

Check Text (C-223346r961878_chk)

Verify the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Account Settings >> Exchange >> Authentication with Exchange Server is set to Kerberos Password Authentication. Use the Windows Registry Editor to navigate to the following key: HKCU\software\policies\microsoft\office\16.0\outlook\security If the value authenticationservice is set to REG_DWORD = 16 (decimal) or 10 (hex), this is not a finding.

Fix Text (F-25007r442258_fix)

Set the policy value for User Configuration >> Administrative Templates >> Microsoft Outlook 2016 >> Account Settings >> Exchange >> Authentication with Exchange Server to Kerberos Password Authentication.