Option Explicit | |
dim oShell, oFSO, dangerousExes, exe, cmdHardCodedHash, cmdDynamicHash, strComputerName, strUserName, strLogFilePath, strSafeDate, _ | |
strSafeTime, strDateTime, strLogFileName, strEventInfo, objLogFile, cmdHashCache, objCmdHashCache, dangerHashCache, _ | |
dangerHashData, mailFile, objDangerHashCache, oFile | |
Set oShell = WScript.CreateObject("WScript.Shell") | |
Set oFSO = CreateObject("Scripting.FileSystemObject") | |
dangerousExes = Array("Magnify.exe", "Narrator.exe", "osk.exe", "sapisvr.exe", "control.exe", "utilman.exe") | |
cmdHardCodedHash = "db 06 c3 53 49 64 e3 fc 79 d2 76 31 44 ba 53 74 2d 7f a2 50 ca 33 6f 4a 0f e7 24 b7 5a af f3 86" | |
cmdDynamicHash = "" | |
strComputerName = oShell.ExpandEnvironmentStrings("%COMPUTERNAME%") | |
strUserName = oShell.ExpandEnvironmentStrings("%USERNAME%") | |
strLogFilePath = "\\server\Logs" | |
strSafeDate = DatePart("yyyy",Date) & Right("0" & DatePart("m",Date), 2) & Right("0" & DatePart("d",Date), 2) | |
strSafeTime = Right("0" & Hour(Now), 2) & Right("0" & Minute(Now), 2) & Right("0" & Second(Now), 2) | |
strDateTime = strSafeDate & "-" & strSafeTime | |
strLogFileName = strLogFilePath & "\" & strComputerName & "-" & strDateTime & "-Accessibility_Defender.txt" | |
cmdHashCache = "C:\cmdHashCache.dat" | |
dangerHashCache = "C:\dangerHashCache.dat" | |
mailFile = "C:\Accessibility_Defender_Warning.mail" | |
'A function to clear the previous dangerCache and create a new one. | |
Function clearCache() | |
If oFSO.FileExists(dangerHashCache) Then | |
oFSO.DeleteFile(dangerHashCache) | |
End If | |
If Not oFSO.FileExists(dangerHashCache) Then | |
oFSO.CreateTextFile(dangerHashCache) | |
End If | |
End Function | |
'A function to create the CMD Hash Cache file. | |
Function getCmdHash() | |
If oFSO.FileExists("C:\Windows\System32\cmd.exe") Then | |
oShell.run "cmd /c CertUtil -hashfile ""C:\Windows\System32\cmd.exe"" SHA256 | find /i /v ""SHA256"" | find /i /v ""certutil"" > " & cmdHashCache, 0, TRUE | |
End If | |
End Function | |
'A function to hash each of the hardcoded files and cache the value. | |
Function getDangerHash() | |
For Each exe In dangerousExes | |
If oFSO.FileExists("C:\Windows\System32\" & exe) Then | |
oShell.run "cmd /c CertUtil -hashfile ""C:\Windows\System32\" & exe & """ SHA256 | find /i /v ""SHA256"" | find /i /v ""certutil"" >> " & dangerHashCache, 0, TRUE | |
End If | |
Next | |
End Function | |
'A function to read the CMD hash cache. | |
Function cmdHashData() | |
If oFSO.FileExists(cmdHashCache) Then | |
Set objCmdHashCache = oFSO.OpenTextFile(cmdHashCache) | |
cmdHashData = objCmdHashCache.ReadAll() | |
objCmdHashCache.close | |
End If | |
End Function | |
'A function to read the Danger hash cache and compare it to the CMD hash cache and hardcoded CMD hash. | |
Function hashMatch() | |
hashMatch = FALSE | |
If oFSO.FileExists(dangerHashCache) Then | |
Set objDangerHashCache = oFSO.OpenTextFile(dangerHashCache) | |
Do While Not objDangerHashCache.AtEndOfStream | |
dangerHashData = objDangerHashCache.ReadLine() | |
If dangerHashData = cmdHashData() Or dangerHashData = cmdHardCodedHash Then | |
hashMatch = TRUE | |
End If | |
loop | |
objDangerHashCache.close | |
End If | |
End Function | |
'A function to create a log file. | |
Function createLog(strEventInfo) | |
If Not (strEventInfo = "") Then | |
Set objLogFile = oFSO.CreateTextFile(strLogFileName, True) | |
objLogFile.WriteLine(strEventInfo) | |
objLogFile.Close | |
End If | |
End Function | |
Function createEmail() | |
If oFSO.FileExists(mailFile) Then | |
oFSO.DeleteFile(mailFile) | |
End If | |
If Not oFSO.FileExists(mailFile) Then | |
oFSO.CreateTextFile(mailFile) | |
End If | |
Set oFile = oFSO.CreateTextFile(mailFile, True) | |
oFile.Write "To: IT@COMPANY.com" & vbNewLine & "From: server@COMPANY.com" & vbNewLine & _ | |
"Subject: COMPANY Accessibility Defender Warning!!!" & vbNewLine & _ | |
"This is an automatic email from the Tru Form Network to notify you that a workstation was defended from Accessibility Tools exploitation." & _ | |
vbNewLine & vbNewLine & "Please log-in and verify that the equipment listed below is secure." & vbNewLine & _ | |
vbNewLine & "USER NAME: " & strUserName & vbNewLine & "WORKSTATION: " & strComputerName & vbNewLine & _ | |
"This check was generated by " & strComputerName & " and is performed when Windows boots." & vbNewLine & vbNewLine & _ | |
"Script: ""Accessibility_Defender.vbs""" | |
oFile.close | |
End Function | |
'A function for running SendMail. | |
Function sendEmail() | |
oShell.run "cmd /c sendmail.exe " & mailFile, 0, TRUE | |
End Function | |
'A function to display a warning message to the user and kill the machine after a specified time. | |
Function killWorkstation() | |
oShell.Run "cmd /c C:\windows\system32\shutdown.exe", 0, false | |
End Function | |
clearCache() | |
getCmdHash() | |
getDangerHash() | |
hashMatch() | |
If hashMatch = TRUE Then | |
createLog("The machine " & strComputerName & " just attempted to execute an Accessibility Tools exploitation!") | |
createEmail() | |
sendEmail() | |
killWorkstation() | |
End If |
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zelon88 commentedAug 27, 2018
This script requires "Fake Sendmail for Windows" by Byron Jones.
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=2ahUKEwjYkJyLqYzdAhXohOAKHaQWD40QFjAAegQICRAB&url=https%3A%2F%2Fwww.glob.com.au%2Fsendmail%2F&usg=AOvVaw1EFXz3aE--b-SKLX8CYH5o