ORCA.109 - Senders are not being allow listed in an unsafe manner.

Contributed by Michael Soule with 4 co-contributorsAll contributors →

Overview

Emails coming from allow listed senders bypass several layers of protection within Exchange Online Protection. If senders are allow listed, they are open to being spoofed from malicious actors.

Remediation action

Remove allow listing on senders.

Related Links

• Microsoft 365 Defender Portal - Anti-spam settings
• Recommended settings for EOP and Office 365 Microsoft Defender for Office 365 security
• Use Anti-Spam Policy Sender/Domain Allow lists

Test Metadata

Field	Value
Test ID	ORCA.109
Severity	Medium
Suite	ORCA
Category	EXO
PowerShell test	Test-ORCA109
Tags	EXO, ORCA, ORCA.109

Source

• Pester test: tests/orca/Test-ORCA109.Tests.ps1
• PowerShell source: powershell/public/orca/Test-ORCA109.ps1