STIGQter: STIG Summary: Microsoft Exchange 2019 Edge Server Security Technical Implementation Guide Version: 2 Release: 2 Benchmark Date: 30 Jan 2025:

The Exchange internet receive connector connections count must be set to default.

DISA Rule

SV-259606r961155_rule

Vulnerability Number

V-259606

Group Title

SRG-APP-000247

Rule Version

EX19-ED-000119

Severity

CAT II

CCI(s)

• CCI-001095 - Manage capacity, bandwidth, or other redundancy to limit the effects of information flooding types of denial of service attacks.

Weight

10

Fix Recommendation

Update the EDSP to reflect the Maximum Inbound connections value.

Open the Exchange Management Shell and enter the following command:

Set-ReceiveConnector -Identity <'IdentityName'> -MaxInboundConnection 5000

Note: The <IdentityName> value must be in quotes.

or

The value as identified by the EDSP that has obtained a signoff with risk acceptance.

Repeat the procedure for each receive connector.

Check Contents

Review the Email Domain Security Plan (EDSP).

Determine the Maximum Inbound connections value.

Open the Exchange Management Shell and enter the following command:

Get-ReceiveConnector | Select-Object -Property Name, Identity, MaxInboundConnection

Identify internet-facing connectors.

For each receive connector, if the value of "MaxInboundConnection" is not set to "5000", this is a finding.

or

If "MaxInboundConnection" is set to a value other than "5000" or is set to unlimited and has signoff and risk acceptance in the EDSP, this is not a finding.

Vulnerability Number

V-259606

Documentable

False

Rule Version

EX19-ED-000119

Severity Override Guidance

Review the Email Domain Security Plan (EDSP).

Determine the Maximum Inbound connections value.

Open the Exchange Management Shell and enter the following command:

Get-ReceiveConnector | Select-Object -Property Name, Identity, MaxInboundConnection

Identify internet-facing connectors.

For each receive connector, if the value of "MaxInboundConnection" is not set to "5000", this is a finding.

or

If "MaxInboundConnection" is set to a value other than "5000" or is set to unlimited and has signoff and risk acceptance in the EDSP, this is not a finding.

Check Content Reference

M

Target Key

5579