Thailand CTF 2017 Write-up : Pickles (250)

250-PICKLES.txt

โจทย์ f.pkl
ccopy_reg
_reconstructor
p0
(c__main__
Foo
p1
c__builtin__
object
p2
Ntp3
Rp4
(dp5
S'y'
p6
S'x\x9c\x1d\x8aA\n\x800\x0c\x04\xbf\xb27/\xe2\x17\xbc\xdagX\x08\xb6X\x8d$)%\xbf7zYf\x87\xd9\xa85\x9e\x91P\xf8!8w\xecB\x18a\x17\xa4\xe9\x82\x89\xd7\xfb\x8012[!\xf9\x93\xec\xe8\xfa\xe9\xc61j\x12\xac\xd1+\xaaa\xb0\x9c\xf1\xd7\x17\x84\xe5\x1f\xad'
p7
sS'x'
p8
S'x\x9c\x1d\x8aA\n\x800\x0c\x04\xbf\xb2WA|\x80\x17\xaf\xf5\xee\x07J-6\x90\x1aI\x94\xe0\xef\r\xc2\x9cf&Uf\x19\x91\xc4\x91\xb5\xe2\x95g\xc1\x8a\xdc\xb1\x0b\x9d\x07<\xf2\x84\xad\x91!\xc8`\ti\xb7\xfe\xadQiq\xc0\x89\x19E\xfa\xa5\xd5\x0c\xf3\xf0\x01\xb9C\x1c\xdf'
p9
sS'z'
p10
S'x\x9c\xf3,Q/V\xc8MUHLO\xcc\xcc\xd3S\xf0T(\xcf,\xceP\xa8\xcc/U(\xc9HUHJ-.Q\xc8OS\xc8)M\xce\x06\xca\x94d\x00E3\x8b\x15\x923\x12srR\xf3\xd2S\x15\xac\\\x00\xd5\xb8\x16a'
p11
sS'b'
p12
S"x\x9c]\x8c1\n\xc30\x10\x04\xbf\xb2\x9d\x1a\xe3\x07\xa4s'H\x9b\x0f\x1c\xd2J\n9\xebDN`\xf2\xfb\x18\x97n\x87\x99\x89T\xb5\x05\xb3\x11\xced=\xa3\x89\x16X\xb9PQ\xa9x;D\xdd\xd0\xc9\xcc\x8ciH\xb6\x0f\xe5\xe4\xe5\xa43P\xf6\xca\x15\x91_\x06\xbf\xcf\x1e\x08Or\xf8\xab1J\xfa\xf8v\xc8/\xfc\x01\xf6d*:"
p13
sS'v'
p14
S'x\x9c\xf3H\xcd\xc9\xc9\xd7Q\xf0T(O\xcc+IMQ(\xc9W(\x01\n)T\xe6\x97*\x94g$\x96(\x94d\xa4*\xa4\xe5$\xa6+d\x16\xeb)x\xa4\x16\xa5\xaa\x17C\xc42\x8b\x8aK\x142\x12s\xd2\xac\x14\xd4\x1d\x032\x93\xb3sR\x1d]\x12+\xd5\x01\x8e\xf6\x1b\xd9'
p15
sb.

วิธีแก้ 
import zlib
import pickle

class Foo(object):
    pass
fpkl = open('250-PICKLES/f.pkl','r').read()
fooObj = pickle.loads(fpkl)
# print dir(fooObj)
# ['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__', 'b', 'v', 'x', 'y', 'z']

print zlib.decompress(fooObj.b)
print zlib.decompress(fooObj.v)
print zlib.decompress(fooObj.x)
print zlib.decompress(fooObj.y)
print zlib.decompress(fooObj.z)

# $ python pickle-pro250.py
# Hello, the second half of the flag is also needed to complete the challenge. Here's the second half: 'KeepsTheHacksAway'
# Hello, I wanted to tell you what the flag is. Here's the first half: 'APickleADay'
# Hello, How are you? I am doing well. This is a long string which we will compress :)
# Hello, I hope you are well. I'm trying to bother you by using long strings. Is it working?
# It's me again. I wish you the best of luck with this challenge :D

Flag: APickleADayKeepsTheHacksAway