NSSCTF Round 16 --- Crypto wp

原创

于 2024-01-18 14:49:40 发布 · 741 阅读

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文章标签：

#web安全 #网络安全 #网络

文章目录

- - pr
  - break

pr

题目：

from Crypto.Util.number import *
import random

flag=plaintext = 'NSSCTF{****************}'
charset = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789'
padding_length = 100 - len(plaintext)

for _ in range(padding_length):
    plaintext += random.choice(charset)

public_exponent = 31413537523
message = bytes_to_long(plaintext.encode())
assert message > (1 << 512)
assert message < (1 << 1024)

prime_p = getPrime(512)
prime_q = getPrime(512)
prime_r = getPrime(512)
n1 = prime_p * prime_q
n2 = prime_q * prime_r
ciphertext1 = pow(message, public_exponent, n1)
ciphertext2 = pow(message, public_exponent, n2)
print('c1='