Pwntools Usage Example

This Python script utilizes pwntools to tackle a RCTF problem. It establishes a connection with a remote server, processes data received, and outputs values Q, T, U, and NUM. The script employs frequency analysis on the data to identify the most frequently occurring positions of a specific x value, ultimately cracking it.

I created a script for solving a simple problem on RCTF.

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from pwn import *
ip = "190.92.234.114"
port = 23334
mclean =lambda l0: l0.decode().split("=")[1].strip()
mlist = lambda T: [int(x) for x in T.replace("[","").replace("]", "").replace(" ","").strip().split(",")]
r = remote(ip, port)
l0 = r.recvline()
# print('first line?', l0) # great man!
q = mclean(l0)
q = int(q)
# but notice you will not like to be fucked up. use safe eval? ast?
l1 = r.recvline()
# print('second line?', l1)
T = mclean(l1)
T = mlist(T)
l2 = r.recvline()
U = mlist(mclean(l2))
# print("third line?", l2)
print("Q?", q)
print()
print("T?", len(T))
print()
print("U?", len(U))
# now crack the x. please observe the original code?
# the shift does not matter so much?
mpos_x = {}
for i in range(90):
t = T[i]
u = U[i]
pos_x = u//t+1
mpos_x.update({pos_x:mpos_x.get(pos_x,0)+1})
mfinalPos = [(key, elem) for key, elem in mpos_x.items()]
mfinalPos.sort(key=lambda x: -x[1])
print("NUM?",mfinalPos[0])
print("COUNT?",mfinalPos[0][1])
# import pyperclip
data =str(mfinalPos[0][0])
# pyperclip.copy(data)
# r.interactive()
r.sendline(data.encode())
flag=r.recvline() #EOFERROR?
print("FLAG?",flag)
# now answer the shit?

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