Microsoft Defender for Endpoint (MDE) must enable Allow or block file.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-275980	SRG-APP-000279	MSDE-00-000550	SV-275980r1119710_rule	2025-07-15	1

Description
Malicious code protection mechanisms include, but are not limited to, antivirus and malware detection software. To minimize potential negative impact to the organization that can be caused by malicious code, it is imperative that malicious code is identified and eradicated. This setting ensures Windows Defender Antivirus is turned on and the cloud-based protection feature is enabled to use the allow or block file feature.

Description

Malicious code protection mechanisms include, but are not limited to, antivirus and malware detection software. To minimize potential negative impact to the organization that can be caused by malicious code, it is imperative that malicious code is identified and eradicated. This setting ensures Windows Defender Antivirus is turned on and the cloud-based protection feature is enabled to use the allow or block file feature.

ℹ️ Check
Access the MDE portal as a user with at least an MDE Administrator or equivalent role: 1. In the navigation pane, select Settings >> Endpoints >> Advanced features (under General). 2. Verify the slide bar for "Allow or block file" is set to "On". If the slide bar for "Allow or block file" is not set to "On", this is a finding.

✔️ Fix
Access the MDE portal as a user with at least an MDE Administrator or equivalent role: 1. In the navigation pane, select Settings >> Endpoints >> Advanced features (under General). 2. Set the slide bar for "Allow or block file" to "On".