[Plaid CTF]

try:
    val = 0
    inp = input("Input value: ")
    count_digits = len(set(inp))
    if count_digits <= 10:          # Make sure it is a number
        val = eval(inp)
    else:
        raise

    if val == secret_value_for_password:
        print(flag)
    else:
        print("Nope. Better luck next time.")
except:
    print("Nope. No hacking.")
    exit(1)

I thought that the flag was filtered, so I kept seeing it, but after a write-up I was devastated. When analyzing this source, I thought secret_value_password should be equal to or less than 10
so if you write long, you have to do it again next time, and even if you write it somewhat, "nope! Hacking" came out and guessing how filtering was done.

 

I was not able to solve it on time.