Sigma rule: Powershell Defender Disable Scan Feature

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-62f577f72097, updated 2024-01-02T00:00:00.000Z.

Rule

Title
Powershell Defender Disable Scan Feature
Status
test
Level
high
Author
Florian Roth (Nextron Systems)
Date
2022-03-03
Modified
2024-01-02
File
rules/windows/process_creation/proc_creation_win_powershell_defender_disable_feature.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects requests to disable Microsoft Defender features using PowerShell commands

Log source

product
windows
category
process_creation

Detection

selection_cli_cmdlet:
    CommandLine|contains:
        - 'Add-MpPreference '
        - 'Set-MpPreference '
selection_cli_option:
    CommandLine|contains:
        - 'DisableArchiveScanning '
        - 'DisableRealtimeMonitoring '
        - 'DisableIOAVProtection '
        - 'DisableBehaviorMonitoring '
        - 'DisableBlockAtFirstSeen '
        - 'DisableCatchupFullScan '
        - 'DisableCatchupQuickScan '
selection_cli_value:
    CommandLine|contains:
        - '$true'
        - ' 1 '
selection_encoded_modifier:
    CommandLine|base64offset|contains:
        # Note: Since this is calculating offsets casing is important
        - 'disablearchivescanning '
        - 'DisableArchiveScanning '
        - 'disablebehaviormonitoring '
        - 'DisableBehaviorMonitoring '
        - 'disableblockatfirstseen '
        - 'DisableBlockAtFirstSeen '
        - 'disablecatchupfullscan '
        - 'DisableCatchupFullScan '
        - 'disablecatchupquickscan '
        - 'DisableCatchupQuickScan '
        - 'disableioavprotection '
        - 'DisableIOAVProtection '
        - 'disablerealtimemonitoring '
        - 'DisableRealtimeMonitoring '
selection_encoded_direct:
    CommandLine|contains:
        - 'RABpAHMAYQBiAGwAZQBSAGUAYQBsAHQAaQBtAGUATQBvAG4AaQB0AG8AcgBpAG4AZwAgA'
        - 'QAaQBzAGEAYgBsAGUAUgBlAGEAbAB0AGkAbQBlAE0AbwBuAGkAdABvAHIAaQBuAGcAIA'
        - 'EAGkAcwBhAGIAbABlAFIAZQBhAGwAdABpAG0AZQBNAG8AbgBpAHQAbwByAGkAbgBnACAA'
        - 'RABpAHMAYQBiAGwAZQBJAE8AQQBWAFAAcgBvAHQAZQBjAHQAaQBvAG4AIA'
        - 'QAaQBzAGEAYgBsAGUASQBPAEEAVgBQAHIAbwB0AGUAYwB0AGkAbwBuACAA'
        - 'EAGkAcwBhAGIAbABlAEkATwBBAFYAUAByAG8AdABlAGMAdABpAG8AbgAgA'
        - 'RABpAHMAYQBiAGwAZQBCAGUAaABhAHYAaQBvAHIATQBvAG4AaQB0AG8AcgBpAG4AZwAgA'
        - 'QAaQBzAGEAYgBsAGUAQgBlAGgAYQB2AGkAbwByAE0AbwBuAGkAdABvAHIAaQBuAGcAIA'
        - 'EAGkAcwBhAGIAbABlAEIAZQBoAGEAdgBpAG8AcgBNAG8AbgBpAHQAbwByAGkAbgBnACAA'
        - 'RABpAHMAYQBiAGwAZQBCAGwAbwBjAGsAQQB0AEYAaQByAHMAdABTAGUAZQBuACAA'
        - 'QAaQBzAGEAYgBsAGUAQgBsAG8AYwBrAEEAdABGAGkAcgBzAHQAUwBlAGUAbgAgA'
        - 'EAGkAcwBhAGIAbABlAEIAbABvAGMAawBBAHQARgBpAHIAcwB0AFMAZQBlAG4AIA'
        - 'ZABpAHMAYQBiAGwAZQByAGUAYQBsAHQAaQBtAGUAbQBvAG4AaQB0AG8AcgBpAG4AZwAgA'
        - 'QAaQBzAGEAYgBsAGUAcgBlAGEAbAB0AGkAbQBlAG0AbwBuAGkAdABvAHIAaQBuAGcAIA'
        - 'kAGkAcwBhAGIAbABlAHIAZQBhAGwAdABpAG0AZQBtAG8AbgBpAHQAbwByAGkAbgBnACAA'
        - 'ZABpAHMAYQBiAGwAZQBpAG8AYQB2AHAAcgBvAHQAZQBjAHQAaQBvAG4AIA'
        - 'QAaQBzAGEAYgBsAGUAaQBvAGEAdgBwAHIAbwB0AGUAYwB0AGkAbwBuACAA'
        - 'kAGkAcwBhAGIAbABlAGkAbwBhAHYAcAByAG8AdABlAGMAdABpAG8AbgAgA'
        - 'ZABpAHMAYQBiAGwAZQBiAGUAaABhAHYAaQBvAHIAbQBvAG4AaQB0AG8AcgBpAG4AZwAgA'
        - 'QAaQBzAGEAYgBsAGUAYgBlAGgAYQB2AGkAbwByAG0AbwBuAGkAdABvAHIAaQBuAGcAIA'
        - 'kAGkAcwBhAGIAbABlAGIAZQBoAGEAdgBpAG8AcgBtAG8AbgBpAHQAbwByAGkAbgBnACAA'
        - 'ZABpAHMAYQBiAGwAZQBiAGwAbwBjAGsAYQB0AGYAaQByAHMAdABzAGUAZQBuACAA'
        - 'QAaQBzAGEAYgBsAGUAYgBsAG8AYwBrAGEAdABmAGkAcgBzAHQAcwBlAGUAbgAgA'
        - 'kAGkAcwBhAGIAbABlAGIAbABvAGMAawBhAHQAZgBpAHIAcwB0AHMAZQBlAG4AIA'
        - 'RABpAHMAYQBiAGwAZQBDAGEAdABjAGgAdQBwAEYAdQBsAGwAUwBjAGEAbgA'
        - 'RABpAHMAYQBiAGwAZQBDAGEAdABjAGgAdQBwAFEAdQBpAGMAawBTAGMAYQBuAA'
        - 'RABpAHMAYQBiAGwAZQBBAHIAYwBoAGkAdgBlAFMAYwBhAG4AbgBpAG4AZwA'
condition: all of selection_cli_* or 1 of selection_encoded_*

False positives (as the rule lists them)

  • Possible administrative activity
  • Other Cmdlets that may use the same parameters

Tags

  • attack.defense-impairment
  • attack.t1685

MITRE ATT&CK ids this rule names

References

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_powershell_defender_disable_feature.yml

Sources and licences

  • SigmaHQ

    "Powershell Defender Disable Scan Feature" by Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_powershell_defender_disable_feature.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: Powershell Defender Disable Scan Feature",
entity page, dataset version ref-62f577f72097, updated 2024-01-02T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/1ec65a5f-9473-4f12-97da-622044d6df21 (accessed 2026-11-03).
Underlying source: SigmaHQ rule 1ec65a5f-9473-4f12-97da-622044d6df21, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.