Tamper Windows Defender Remove-MpPreference

Severity: high
Author: Nasreddine Bencherchali (Nextron Systems)
Source: upstream

Detects attempts to remove Windows Defender configurations using the 'MpPreference' cmdlet

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1562.001` Impair Defenses: Disable or Modify Tools

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation
Security-Auditing	4688	A new process has been created.

Stages and Predicates

Stage 1: `all of selection_remove`

CommandLine|contains: Remove-MpPreference

Stage 2: `all of selection_tamper`

or:
CommandLine|contains: '-AttackSurfaceReductionRules_Actions '
CommandLine|contains: '-AttackSurfaceReductionRules_Ids '
CommandLine|contains: '-CheckForSignaturesBeforeRunningScan '
CommandLine|contains: '-ControlledFolderAccessProtectedFolders '

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`CommandLine`	match	`-AttackSurfaceReductionRules_Actions` `-AttackSurfaceReductionRules_Ids` `-CheckForSignaturesBeforeRunningScan` `-ControlledFolderAccessProtectedFolders` `Remove-MpPreference`