The Exchange Mail Store storage quota must issue a warning.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-70005	EX13-MB-000165	SV-84627r1_rule		Low

Description
Mail quota settings control the maximum sizes of a user’s mailbox and the system’s response if these limits are exceeded. Mailbox data that is not monitored against a quota increases the risk of mail loss due to filled disk space, which can also render the system unavailable. There are multiple controls, which supply graduated levels of opportunity to respond before risking data loss. This control sends the user a warning message that the mailbox is reaching its limit. The user at this point can still send and receive email. Note: Best practice is to send this warning when the mailbox reaches 75 percent of capacity.

Description

Mail quota settings control the maximum sizes of a user’s mailbox and the system’s response if these limits are exceeded. Mailbox data that is not monitored against a quota increases the risk of mail loss due to filled disk space, which can also render the system unavailable. There are multiple controls, which supply graduated levels of opportunity to respond before risking data loss. This control sends the user a warning message that the mailbox is reaching its limit. The user at this point can still send and receive email. Note: Best practice is to send this warning when the mailbox reaches 75 percent of capacity.

STIG	Date
MS Exchange 2013 Mailbox Server Security Technical Implementation Guide	2019-09-25

Details

Check Text ( C-70479r1_chk )
Review the Email Domain Security Plan (EDSP). Determine the value for Issue Warning Quota. Open the Exchange Management Shell and enter the following command: Get-MailboxDatabase \| Select Name, Identity, IssueWarningQuota If the value of IssueWarningQuota is not set to the site's Issue Warning Quota, this is a finding.

Fix Text (F-76241r1_fix)
Update the EDSP. Open the Exchange Management Shell and enter the following command: Set-MailboxDatabase -Identity <'IdentityName'> -IssueWarningQuota <'WarningQuota'> Note: The and values must be in quotes.