A Windows Defender Antivirus policy is created and assigned

Overview

If policies for Microsoft Defender Antivirus aren’t properly configured and assigned in Intune, threat actors can exploit unprotected endpoints to execute malware, disable antivirus protections, and persist within the environment. Without enforced antivirus policies, devices operate with outdated definitions, disabled real-time protection, or misconfigured scan schedules. These gaps allow attackers to bypass detection, escalate privileges, and move laterally across the network. The absence of antivirus enforcement undermines device compliance, increases exposure to zero-day threats, and can result in regulatory noncompliance. Attackers leverage these weaknesses to maintain persistence and evade detection, especially in environments lacking centralized policy enforcement.

Enforcing Defender Antivirus policies ensures consistent protection against malware, supports real-time threat detection, and aligns with Zero Trust by maintaining a secure and compliant endpoint posture.

Remediation

Configure and assign Intune policies for Microsoft Defender Antivirus to enforce real-time protection, maintain up-to-date definitions, and reduce exposure to malware:

• Configure Intune policies to manage Microsoft Defender Antivirus
• Assign policies in Intune

Run it

The check runs as part of the whole assessment, with the ZeroTrustAssessment module installed:

Install-Module ZeroTrustAssessment -Scope CurrentUser
Connect-Maester
Invoke-Maester -Pack ZTA -SkipBuiltIn

Leave out -SkipBuiltIn to run Maester’s own checks in the same run.

About this check

Severity	High
Effort to fix	Low
Impact on users	Low
Pillar	Devices
Category	Device management
Product	Intune
Feature	Endpoint security
Area	Devices and endpoints
ATT&CK	T1204.002 Malicious File, T1685 Disable or Modify Tools
Licence	Intune
Tenant	Workforce

Product, feature, area and ATT&CK are Maester’s: the assessment does not record them, so Maester keeps them in the pack’s taxonomy.json.

A Microsoft check, part of the Zero Trust Assessment pack. Text from ZeroTrustAssessment 3.1.0, © Microsoft, MIT licence.