Title

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

Discussion

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.

Check Content

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

Open the Exchange Management Shell and enter the following command: Set-SenderFilterConfig -Enabled $true

Additional Identifiers

Rule ID: SV-221248r879653_rule

Vulnerability ID: V-221248

Group Title: SRG-APP-000261

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.