#hsctf8 from Crypto.Util.number import * import random import sympy flag = open('flag.txt','rb').read() p,q = getPrime(1024),getPrime(1024) e = 0x10001 n = p*q m = random.randrange(0,n) c = pow(m,e,n) d = sympy.mod_inverse(e,(p-1)*(q-1)) d…

#hsctf8 import time from Crypto.Util.number import * flag = open('flag.txt','r').read() p = getPrime(1024) q = getPrime(1024) e = 2**16+1 n=p*q ct=[] for ch in flag: ct.append((ord(ch)^e)%n) print(n) print(e) print(ct) RSA import ast with …

#hsctf8 from Crypto.Cipher import AES from Crypto.Random import * from Crypto.Util.Padding import * import random flag = open('flag.txt','rb').read() print("Hello, I'm Bernard the biologist!") print() print("My friends love to keyboard spa…

#hsctf8 import random var("x y") flag = int(open('flag.txt','rb').read().hex(),16) xs = [random.randint(1,256) for i in range(9)] ys = [random.randint(1,256) for i in range(9)] assert not any([xs[i]==ys[i] for i in range(9)]) c = [random.r…

#hsctf8 flag = open('flag.txt','r').read() #open the flag assert flag[0:5]=="flag{" and flag[-1]=="}" #flag follows standard flag format letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" encoded = "" for character in flag[5:-1]: encoded+=letters[(let…

#hsctf8 from collections import Counter from Crypto.Util.number import * import sys import random import sympy flag = open('flag.txt','rb').read() print("Loading... this may take a while.") p,q = getPrime(4096),getPrime(4096) e = 0x10001 n…

#hsctf8 from sage.all import * import random flag = open('flag.txt','rb').read() class prng: co = [random_prime(2**64-1,False,2**63) for i in range(100)] n = int(next_prime(2**64)) def __init__(self): self.s = [random.randint(1,self.n) for…

#hsctf8 from Crypto.Util.number import * import binascii flag = open('flag.txt','rb').read() p = getPrime(1024) q = getPrime(1024) n = p*q e = 2**16+1 pt = int(binascii.hexlify(flag).decode(),16) print(p>>512) print(q%(2**512)) print(n, e)…

#hsctf8 from Crypto.Util.number import * import random import math flag = open('flag.txt','rb').read() while 1: p = getPrime(512) q = getPrime(512) if (p<q or p>2*q): continue break n = p**2*q while 1: a = random.randint(2,n-1) if pow(a,p-1,p**2)!</q>…

#hsctf8 import random var("x y") flag = int(open('flag.txt','rb').read().hex(),16) xs = [random.randint(1,256) for i in range(9)] ys = [random.randint(1,256) for i in range(9)] assert not any([xs[i]==ys[i] for i in range(9)]) c = [random.r…

#hsctf8 Zn = Zmod(26) key = [ [16,25,8], [14,19,5], [15,17,3], ] invkey = matrix(Zn, key)^-1 plaintext = b"rtca{vbuhp_kaiq_gfj_nx_rda_ujw}" plaintext = [x - ord('a') for x in plaintext if ord('a') <= x <= ord('z')] print(plaintext) flag = …