PowerShell Script with Discovery Capabilities

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Identifies the use of Cmdlets and methods related to discovery activities. Attackers can use these to perform various situational awareness related activities, like enumerating users, shares, sessions, domain trusts, groups, etc.

Rule type: query

Rule indices:

  • winlogbeat-*
  • logs-windows.*

Severity: low

Risk score: 21

Runs every: 60m

Searches indices from: now-119m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References: None

Tags:

  • Domain: Endpoint
  • OS: Windows
  • Use Case: Threat Detection
  • Tactic: Collection
  • Tactic: Discovery
  • Data Source: PowerShell Logs
  • Rule Type: BBR

Version: 1

Rule authors:

  • Elastic

Rule license: Elastic License v2

Investigation guide

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Rule query

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event.category:process and host.os.type:windows and
  powershell.file.script_block_text : (
    (
      ("Get-ItemProperty" or "Get-Item") and "-Path"
    ) or
    (
      "Get-ADDefaultDomainPasswordPolicy" or
      "Get-ADDomain" or "Get-ComputerInfo" or
      "Get-Disk" or "Get-DnsClientCache" or
      "Get-GPOReport" or "Get-HotFix" or
      "Get-LocalUser" or "Get-NetFirewallProfile" or
      "get-nettcpconnection" or "Get-NetAdapter" or
      "Get-PhysicalDisk" or "Get-Process" or
      "Get-PSDrive" or "Get-Service" or
      "Get-SmbShare" or "Get-WinEvent"
    ) or
    (
      ("Get-WmiObject" or "gwmi" or "Get-CimInstance" or
       "gcim" or "Management.ManagementObjectSearcher" or
       "System.Management.ManagementClass" or
       "[WmiClass]" or "[WMI]") and
      (
        "AntiVirusProduct" or "CIM_BIOSElement" or "CIM_ComputerSystem" or "CIM_Product" or "CIM_DiskDrive" or
        "CIM_LogicalDisk" or "CIM_NetworkAdapter" or "CIM_StorageVolume" or "CIM_OperatingSystem" or
        "CIM_Process" or "CIM_Service" or "MSFT_DNSClientCache" or "Win32_BIOS" or "Win32_ComputerSystem" or
        "Win32_ComputerSystemProduct" or "Win32_DiskDrive" or "win32_environment" or "Win32_Group" or
        "Win32_groupuser" or "Win32_IP4RouteTable" or "Win32_logicaldisk" or "Win32_MappedLogicalDisk" or
        "Win32_NetworkAdapterConfiguration" or "win32_ntdomain" or "Win32_OperatingSystem" or
        "Win32_PnPEntity" or "Win32_Process" or "Win32_Product" or "Win32_quickfixengineering" or
        "win32_service" or "Win32_Share" or "Win32_UserAccount"
      )
    ) or
    (
      ("ADSI" and "WinNT") or
      ("Get-ChildItem" and "sysmondrv.sys") or
      ("::GetIPGlobalProperties()" and "GetActiveTcpConnections()") or
      ("ServiceProcess.ServiceController" and "::GetServices") or
      ("Diagnostics.Process" and "::GetProcesses") or
      ("DirectoryServices.Protocols.GroupPolicy" and ".GetGPOReport()") or
      ("DirectoryServices.AccountManagement" and "PrincipalSearcher") or
      ("NetFwTypeLib.NetFwMgr" and "CurrentProfile") or
      ("NetworkInformation.NetworkInterface" and "GetAllNetworkInterfaces") or
      ("Automation.PSDriveInfo") or
      ("Microsoft.Win32.RegistryHive")
    ) or
    (
      "Get-ItemProperty" and
      (
        "\Control\SecurityProviders\WDigest" or
        "\microsoft\windows\currentversion\explorer\runmru" or
        "\Microsoft\Windows\CurrentVersion\Policies\System\Kerberos\Parameters" or
        "\Microsoft\Windows\CurrentVersion\Uninstall" or
        "\Microsoft\Windows\WindowsUpdate" or
        "Policies\Microsoft\Windows\Installer" or
        "Software\Microsoft\Windows\CurrentVersion\Policies" or
        ("\Services\SharedAccess\Parameters\FirewallPolicy" and "EnableFirewall") or
        ("Microsoft\Windows\CurrentVersion\Internet Settings" and "proxyEnable")
      )
    ) or
    (
      ("Directoryservices.Activedirectory" or
      "DirectoryServices.AccountManagement") and
      (
        "Domain Admins" or "DomainControllers" or
        "FindAllGlobalCatalogs" or "GetAllTrustRelationships" or
        "GetCurrentDomain" or "GetCurrentForest"
      ) or
      "DirectoryServices.DirectorySearcher" and
      (
        "samAccountType=805306368" or
        "samAccountType=805306369" or
        "objectCategory=group" or
        "objectCategory=groupPolicyContainer" or
        "objectCategory=site" or
        "objectCategory=subnet" or
        "objectClass=trustedDomain"
      )
    ) or
    (
      "Get-Process" and
      (
        "mcshield" or "windefend" or "savservice" or
        "TMCCSF" or "symantec antivirus" or
        "CSFalcon" or "TmPfw" or "kvoop"
      )
    )
  ) and not user.id : ("S-1-5-18" or "S-1-5-19" or "S-1-5-20")
  and not file.path : (*WindowsPowerShell*Modules*.psd1 or *WindowsPowerShell*Modules*.psm1)

Framework: MITRE ATT&CKTM