STIGQter: STIG Summary: Microsoft Exchange 2019 Mailbox Server Security Technical Implementation Guide Version: 2 Release: 3 Benchmark Date: 02 Jul 2025:

Exchange mail quota settings must not restrict sending mail.

DISA Rule

SV-259676r961152_rule

Vulnerability Number

V-259676

Group Title

SRG-APP-000246

Rule Version

EX19-MB-000123

Severity

CAT III

CCI(s)

• CCI-001094 - Restrict the ability of individuals to launch organization-defined denial of service attacks against other systems.

Weight

10

Fix Recommendation

Update the EDSP to specify the value for the Prohibit Send Quota limit or verify that this information is documented by the organization.

Open the Exchange Management Shell and enter the following command:

Set-MailboxDatabase -Identity <'IdentityName'> -ProhibitSendQuota <'QuotaLimit'>

Note: The <IdentityName> and <QuotaLimit> values must be in quotes.

Check Contents

Review the Email Domain Security Plan (EDSP) or document that contains this information.

Determine the value for the Prohibit Send Quota limit.

Open the Exchange Management Shell and enter the following command:

Get-MailboxDatabase | Select-Object -Property Name, Identity, ProhibitSendQuota

If the value of "ProhibitSendQuota" is not set to the site's Prohibit Send Quota limit, this is a finding.

Vulnerability Number

V-259676

Documentable

False

Rule Version

EX19-MB-000123

Severity Override Guidance

Review the Email Domain Security Plan (EDSP) or document that contains this information.

Determine the value for the Prohibit Send Quota limit.

Open the Exchange Management Shell and enter the following command:

Get-MailboxDatabase | Select-Object -Property Name, Identity, ProhibitSendQuota

If the value of "ProhibitSendQuota" is not set to the site's Prohibit Send Quota limit, this is a finding.

Check Content Reference

M

Target Key

5580