Microsoft Defender AV must randomize scheduled task times.

Documentable No

Rule ID SV-278659r1144055_rule

CCI References

CCI-001242

Discussion

In Microsoft Defender Antivirus, randomize the start time of the scan to any interval from 0 to 23 hours. By default, scheduled tasks begin at a random time within four hours of the time specified in Task Scheduler.

Check Procedure

Verify the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Randomize scheduled task times 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

Criteria: If the value "RandomizeScheduleTaskTimes" is REG_DWORD = 1, this is not a finding.

If the value is 0, this is a finding.

Fix Action

Set the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> Microsoft Defender Antivirus >> Randomize scheduled task times to "Enabled".

Click "OK".

Click "Apply".