The Telnet Client must not be installed.

From Windows Server 2016 Security Technical Implementation Guide

Associated with: CCI-000382

SV-87947r1_rule The Telnet Client must not be installed.

Vulnerability discussion

Unnecessary services increase the attack surface of a system. Some of these services may not support required levels of authentication or encryption or may provide unauthorized access to the system.

Check content

Open "PowerShell". Enter "Get-WindowsFeature | Where Name -eq Telnet-Client". If "Installed State" is "Installed", this is a finding. An Installed State of "Available" or "Removed" is not a finding.

Fix text

Uninstall the "Telnet Client" feature. Start "Server Manager". Select the server with the feature. Scroll down to "ROLES AND FEATURES" in the right pane. Select "Remove Roles and Features" from the drop-down "TASKS" list. Select the appropriate server on the "Server Selection" page and click "Next". Deselect "Telnet Client" on the "Features" page. Click "Next" and "Remove" as prompted.

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