misc

Cyber Apocalypse 2021

Alien Camp

Solved By : thewhiteh4t

• The challenge server sends a randomized set of emoji and value pair
• We can get all pairs from option 1
• After getting all pairs we can start calculating values for each question
• If you get EOF Error just restart the script
• After 500 questions we get the flag
``````    #!/usr/bin/env python3

from pwn import *

host = '46.101.82.40'
port = 32156
conn = remote(host, port)
conn.recvuntil('>').decode()
print('[+] Getting some help...')
conn.send('1\n')
out = conn.recvuntil('\n>').decode()
help_arr = out.split('\n')
help_txt = help_arr[2]
store = help_txt.split(' ')
emojis = []
vals = []
new_store = {}
counter = 0
for item in store[0::3]:
if len(item) > 0:
emojis.append(item)
for item in store [2::3]:
vals.append(item)
for emo in emojis:
new_store[emo] = vals[emojis.index(emo)]
if len(new_store) != 0:
print('[+] Help recieved!')
conn.send('2\n')
def solve(conn):
global counter
if counter != 500:
q_txt = conn.recvuntil('?').decode()
q_txt = q_txt.split('\n')
q_txt = q_txt[-1]
print(f'[Q:{counter}] {q_txt}')
q_txt = q_txt.split('  =')
q_txt = q_txt[0]
q_emo = q_txt.split(' ')
for elem in q_emo:
if elem in new_store:
q_txt = q_txt.replace(elem, new_store[elem])
ans = eval(q_txt)
print(f'[+] Sending {ans}')
conn.send(str(ans) + '\n')
else:
flag = conn.recvuntil('}').decode()
print(flag)
conn.close()
counter += 1
while counter <= 500:
solve(conn)
``````
Published on : 24 Apr 2021
misc