The Exchange Simple Mail Transfer Protocol (SMTP) Sender filter must be enabled.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-221248	EX16-ED-000520	SV-221248r612603_rule		Medium

Description
Email system availability depends in part on best practices strategies for setting tuning configurations. Careful tuning reduces the risk that system or network congestion will contribute to availability impacts. Filters that govern inbound email evaluation can significantly reduce spam, phishing, and spoofed emails. Filters for messages from blank senders, known spammers, or zero-day attack modifications must be enabled to be effective. Failure to enable the filter will result in no action taken. This setting should always be enabled.

Description

Email system availability depends in part on best practices strategies for setting tuning configurations. Careful tuning reduces the risk that system or network congestion will contribute to availability impacts. Filters that govern inbound email evaluation can significantly reduce spam, phishing, and spoofed emails. Filters for messages from blank senders, known spammers, or zero-day attack modifications must be enabled to be effective. Failure to enable the filter will result in no action taken. This setting should always be enabled.

STIG	Date
Microsoft Exchange 2016 Edge Transport Server Security Technical Implementation Guide	2020-12-10

Details

Check Text ( C-22963r411870_chk )
This requirement is N/A for SIPR enclaves. This requirement is N/A if the organization subscribes to EEMSG or other similar DoD enterprise protections for email services. Open the Exchange Management Shell and enter the following command: Get-SenderFilterConfig \| Select Name, Enabled If the value of "Enabled" is not set to "True", this is a finding.

Fix Text (F-22952r411871_fix)
Open the Exchange Management Shell and enter the following command: Set-SenderFilterConfig -Enabled $true