CISA.MS.EXO.15.2 - Direct download links SHOULD be scanned for malware.

Contributed by Michael Soule with Thomas SchmidtAll contributors →

Overview

Direct download links SHOULD be scanned for malware.

Rationale: URLs in emails may direct users to download and run malware. Scanning direct download links in real-time for known malware and blocking access can prevent users from infecting their devices.

Remediation action:

1. Sign in to Microsoft 365 Defender.
2. In the left-hand menu, go to Email & Collaboration > Policies & Rules.
3. Select Threat Policies.
4. From the Templated policies section, select Preset Security Policies.
5. Under either Standard protection or Strict protection, select Manage protection settings.
6. Select Next until you reach the Apply Defender for Office 365 protection page.
7. On the Apply Defender for Office 365 protection page, select All recipients.
8. (Optional) Under Exclude these recipients, add Users and Groups to be exempted from the preset policies.
9. Select Next on each page until the Review and confirm your changes page.
10. On the Review and confirm your changes page, select Confirm.

Related links

• Defender admin center - Preset security policies
• CISA 15 Link Protection - MS.EXO.15.2
• CISA ScubaGear Rego Reference

Test Metadata

Field	Value
Test ID	CISA.MS.EXO.15.2
Severity	High
Suite	CISA
Product	Exchange Online
Related products	Defender
Feature	Safe Links
Area	Email and collaboration protection
Resource type	Tenant
User impact	Low
Implementation cost	Low
MITRE ATT&CK	T1204.001 Malicious Link, T1566.002 Spearphishing Link
Supports benchmark	CISA SCuBA Secure Configuration Baselines for Microsoft 365 (version ScubaGear main, 2026-10-11), requirement MS.EXO.15.2
Criticality	SHOULD
Upstream requirement	Moved to MS.SECURITYSUITE.7.2v1 (was MS.EXO.15.2v1)
Supports controls	cisa-scuba:MS.EXO.15.2, nist-800-53-r5:SI-3
PowerShell test	Test-MtCisaSafeLinkDownloadScan
Services	ExchangeOnline, Graph, SecurityCompliance
Compatible licenses	ATP_ENTERPRISE

Source

• Test: tests/cisa/exchange/Test.CISA.MS.EXO.15.2.ps1
• Documentation: tests/cisa/exchange/Test.CISA.MS.EXO.15.2.md