Sender reputation filter must identify SPAM block level.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-33638	Exch-2-324	SV-44058r1_rule	ECSC-1	Medium

Description
By performing filtering at the perimeter, up to 90% of SPAM, malware, and other undesirable messages are eliminated from the message stream rather than admitting them into the mail server environment. Sender reputation is anti-SPAM functionality that blocks messages according to many characteristics of the sender. Sender reputation relies on persisted data about the sender to determine what action, if any, to take on an inbound message. This setting enables the threshold at which an email will be considered SPAM.

Description

By performing filtering at the perimeter, up to 90% of SPAM, malware, and other undesirable messages are eliminated from the message stream rather than admitting them into the mail server environment. Sender reputation is anti-SPAM functionality that blocks messages according to many characteristics of the sender. Sender reputation relies on persisted data about the sender to determine what action, if any, to take on an inbound message. This setting enables the threshold at which an email will be considered SPAM.

STIG	Date
MS Exchange 2010 Edge Transport Server STIG	2018-09-17

Details

Check Text ( C-41747r3_chk )
Open the Exchange Management Shell and enter the following command: Get-SenderReputationConfig \| Select SrlBlockThreshold If the value of 'SrlBlockThreshold' is not set to '6', this is a finding. If the value of 'SrlBlockThreshold' is set to a value other than 6 and has signoff and risk acceptance in the EDSP, this is not a finding.

Fix Text (F-37530r1_fix)
Open the Exchange Management Shell and enter the following command: Set-SenderReputationConfig -SrlBlockThreshold 6. If an alternate value is desired, obtain signoff with risk acceptance and document in the EDSP.