DroidCon, Sect-ctf 2019, RC4 decrypt

solve_droidcon.py

from arc4 import ARC4

data='\xef\x8eX7 CD\xcc\xfb!\x03@\xf5\x10\xf8 \x18\x986\xc09\xcf\x87/\xc2h\xd1\x94\xc6\x83\xfb;aG\xfat\n\xda^\x0f\xb8\xe1]d\xb6=\xd7\xa4\x0216:\x0f\xf8\xf6j\xdeN\xc3\xd5\x82z$^\xfa\xc0\xea\xab\x14\xf1qB\x80\x9c\xc5Z\xd5\xf8\xc0(H\\2\x17_\xa0\xef\xf4\x16q\x00\xbd\x17q\xfd\x10\xef\x17\xe6\xb6\x86\xea[\xb7:\x1c\x85\x8evJ!\x1a\x9d\x00\xefP\x9eml=\x13*g3\x7f\xc7\x97\xb4\xb6'

def decrypt(key):
        arc4 = ARC4(key)
        config = arc4.decrypt(data)
        config = str(config)
        if('flag' in config):
                print(config, key)

end1="0NOTCOOLMANc"
end2="1NOTCOOLMANc"
end3="0STEALCOINZc"
end4="1STEALCOINZc"
alpha='0123456789abcdefghijklmnopqrstuvwxyz'
# alpha="abcdefghijklmnopqrstuvwxyz"
for i in alpha:
        for j in alpha:
                for k in alpha:
                        for l in alpha:
                                string1=i+j+k+l
                                decrypt(string1+end1)
                                decrypt(string1+end2)
                                decrypt(string1+end3)
                                decrypt(string1+end4)
        print(i+" alphabet completed")