Query: alert when Detects base64 encoded "MpPreference" PowerShell cmdlet code that tries to modifies or tamper with Windows Defender AV
Matching passage: Sigma rule: Detects base64 encoded "MpPreference" PowerShell cmdlet code that tries to modifies or tamper with Windows Defender AV. Logsource: windows / process_creation. Rule: title: Powershell Base64 Encoded MpPreference Cmdlet id: c6fb44c6-71f5-49e6-9462-1425d328aee3 status: test description: Detects base64 encoded "MpPreference" PowerShell cmdlet code that tries to modifies or tamper with Windows Defender AV references: - https://learn.microsoft.com/en-us/defender-endpoint/configure-process-opened-file-exclusions-microsoft-defender-antivirus - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1562.001/T1562.001.md - https://twitter.com/AdamTheAnalyst/status/1483497517119590403 author: Florian Roth (Nextron Systems) date: 2022-03-04 modified: 2023-01-30 tags: - attack.defense-impairment - attack.t1685 logsource: category: process_creation product: windows detection: selection: - CommandLine|base64offset|contains: - 'Add-MpPreference ' - 'Set-MpPreference ' - 'add-mppreference ' - 'set-mppreference ' - CommandLine|contains: - QQBkAGQALQBNAHAAUAByAGUAZgBlAHIAZQBuAGMAZQAgA - EAZABkAC0ATQBwAFAAcgBlAGYAZQByAGUAbgBjAGUAIA - BAGQAZAAtAE0AcABQAHIAZQBmAGUAcgBlAG4AYwBlACAA - UwBlAHQALQBNAHAAUAByAGUAZgBlAHIAZQBuAGMAZQAgA - MAZQB0AC0ATQBwAFAAcgBlAGYAZQByAGUAbgBjAGUAIA - TAGUAdAAtAE0AcABQAHIAZQBmAGUAcgBlAG4AYwBlACAA - YQBkAGQALQBtAHAAcAByAGUAZgBlAHIAZQBuAGMAZQAgA - EAZABkAC0AbQBwAHAAcgBlAGYAZQByAGUAbgBjAGUAIA - hAGQAZAAtAG0AcABwAHIAZQBmAGUAcgBlAG4AYwBlACAA - cwBlAHQALQBtAHAAcAByAGUAZgBlAHIAZQBuAGMAZQAgA - MAZQB0AC0AbQBwAHAAcgBlAGYAZQByAGUAbgBjAGUAIA - zAGUAdAAtAG0AcABwAHIAZQBmAGUAcgBlAG4AYwBlACAA condition: selection falsepositives: - Unknown level: high
Near-miss passage: Sigma rule: Detects Windows Installer service (msiexec.exe) trying to install MSI packages with SYSTEM privilege. Logsource: windows / process_creation. Rule: title: Always Install Elevated Windows Installer id: cd951fdc-4b2f-47f5-ba99-a33bf61e3770 status: test description: Detects Windows Installer service (msiexec.exe) trying to install MSI packages with SYSTEM privilege references: - https://image.slidesharecdn.com/kheirkhabarovoffzonefinal-181117201458/95/hunting-for-privilege-escalation-in-windows-environment-48-638.jpg author: Teymur Kheirkhabarov (idea), Mangatas Tondang (rule), oscd.community date: 2020-10-13 modified: 2024-12-01 tags: - attack.privilege-escalation - attack.t1548.002 logsource: product: windows category: process_creation detection: selection_user: User|contains: - AUTHORI - AUTORI selection_image_1: Image|contains|all: - \Windows\Installer\ - msi Image|endswith: tmp selection_image_2: Image|endswith: \msiexec.exe IntegrityLevel: - System - S-1-16-16384 filter_installer: ParentImage: C:\Windows\System32\services.exe filter_repair: - CommandLine|endswith: \system32\msiexec.exe /V - ParentCommandLine|endswith: \system32\msiexec.exe /V filter_sophos: ParentImage|startswith: C:\ProgramData\Sophos\ filter_avira: ParentImage|startswith: C:\ProgramData\Avira\ filter_avast: ParentImage|startswith: - C:\Program Files\Avast Software\ - C:\Program Files (x86)\Avast Software\ filter_google_update: ParentImage|startswith: - C:\Program Files\Google\Update\ - C:\Program Files (x86)\Google\Update\ condition: 1 of selection_image_* and selection_user and not 1 of filter_* falsepositives: - System administrator usage - Anti virus products - WindowsApps located in "C:\Program Files\WindowsApps\" level: medium