d3ctf-2021-scientific_calculator

This is a archive of the challenge "scientific calculator" in D^3CTF 2021.

Environment

Python 3.9.1+ from Debian bullseye (testing) package manager in 2021/3/7.

In fact, Python3.9.1+ nearly equals to Python3.9.2, both of them fixed same security vulnerabilities.

For this challenge, The Python 3.9.2 from Docker Hub may not works properly, because of its strange dynamic libraries.

Deployment

Just run python calculator.py

Challenge description

This is a super-safe and powerful scientific calculator.

import cmath

# you can play with complex number
n = 1 + 1j
n = cmath.log(n ** 4)
print(n)

# ... and definite integral
f = lambda x: x ** 2
bottom = 0
top = 1

result = 0
unit = 1e-5

while bottom < top:
    result += f(bottom) * unit
    bottom += unit

print(result)

# but you can't control my server :P
# import os
# os.system('/bin/sh')

Solution

Waiting for PSRT 's response...