MS Exchange 2010 Edge Transport Server STIG Version Comparison

There are 6 differences between versions v1 r13 (Oct. 26, 2018) (the "left" version) and v1 r15 (April 26, 2019) (the "right" version).

Check Exch-2-011 was removed from the benchmark in the "right" version. The text below reflects the old wording.

This check's original form is available here.

Title

Global inbound message size must be controlled.

Check Content

Obtain the Email Domain Security Plan (EDSP) and locate the global maximum message receive size. Open the Exchange Management Shell and enter the following command: Get-TransportConfig | Select Identity, MaxReceiveSize If the value of 'MaxReceiveSize' is set to 10MB, this is not a finding. If the value of 'MaxReceiveSize' is set to an alternate value, and has signoff and risk acceptance in the EDSP, this is not a finding. If the value of 'MaxReceiveSize' is set to “Unlimited”, this is a finding.

Discussion

Email system availability depends in part on best practices strategies for setting tuning configurations. Message size limits should be set to 10 megabytes at most, but often are smaller, depending on the organization. The key point in message size is that it should be set globally, and it should not be set to ‘unlimited’. Selecting ‘unlimited’ on either field is likely to result in abuse and can contribute to excessive server disk space consumption. Message size limits may also be applied on SMTP connectors, Public Folders, and on the user account under AD. Changes at these lower levels are discouraged, as the single global setting is usually sufficient. This practice prevents conflicts that could impact availability and it simplifies server administration.

Fix

Open the Exchange Management Shell and enter the following command: Set-TransportConfig -MaxReceiveSize 10MB If an alternate value is desired, obtain signoff with risk acceptance and document in the EDSP.