Microsoft Defender AV must enable the file hash computation feature.

This policy drives the ability to enforce Indicators of Compromise (IoC) by using file hash allow/block indicators.

Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> MpEngine >> Enable file hash computation feature is set to "Enabled"; otherwise, this is a finding. Procedure: Use the Windows Registry Editor to navigate to the following key: HKLM\Software\Policies\Microsoft\Windows Defender\MpEngine Criteria: If the value "EnableFileHashComputation" is REG_DWORD = 1, this is not a finding. If the value is 0, this is a finding.

Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> MpEngine >>Enable file hash computation feature to "Enabled".