HNCTF 2022 WEEK1

[HNCTF 2022 Week1]超级签到

str2是

编写脚本

str2 = '{hello_world}'
print(str2.replace(chr(111),chr(48)))
#{hell0_w0rld}

[HNCTF 2022 Week1]贝斯是什么乐器啊？

enc为

码表为

脚本为

a = "NRQ@PAu;8j[+(R:2806.i"
flag = ""
for i in range(len(a)):
    flag += chr(ord(a[i]) + i)
print(flag)
#NSSCTF{B@se64_HAHAHA}

[HNCTF 2022 Week1]X0r

编写脚本

arr = [0x3FE,0x3EB,0x3EB,0x3FB,0x3E4,0x3F6,0x3D3,0x3D0,0x388,0x3CA,0x3EF,0x389,0x3CB,0x3EF,0x3CB,0x388,0x3EF,0x3D5,0x3D9,0x3CB,0x3D1,0x3CD]
flag = ""
for i in range(len(arr)):
    flag += chr((arr[i] - 900) ^ 0x34)
print(flag)
#NSSCTF{x0r_1s_s0_easy}

[HNCTF 2022 Week1]你知道什么是Py嘛？

s = str(input("please input your flag:"))


arr=[29, 0, 16, 23, 18, 61, 43, 41, 13, 28, 88, 94, 49, 110, 66, 44, 43, 28, 91, 108, 61, 7, 22, 7, 43, 51, 44, 46, 9, 18, 20, 6, 2, 24]

if(len(s)!=35  or s[0]!='N'):
    print("error")
    exit(0)

for i in range(1,len(s)):
    if(ord(s[i-1])^ord(s[i])!=arr[i-1]):
        print("error!")
        exit(0)
print("right!")

编写脚本

print(ord('N'))
arr=[78, 29, 0, 16, 23, 18, 61, 43, 41, 13, 28, 88, 94, 49, 110, 66, 44, 43, 28, 91, 108, 61, 7, 22, 7, 43, 51, 44, 46, 9, 18, 20, 6, 2, 24] 
flag = 'N'
for i in range(1,len(arr)):     
    flag += chr(ord(flag[i-1]) ^ arr[i])
print(flag)
#NSSCTF{Pyth0n_1s_th3_best_l@nguage}

[HNCTF 2022 Week1]CrackMe

关键是这个

如果Str1不等于Str2的话，就会弹出“ThisSerialSuck”，反之则会弹出Text

在这下断点，动调

名字CrackMe，Serial随便输

[HNCTF 2022 Week1]给阿姨倒一杯Jvav

Class文件

拖进jadx中

编写脚本

key = [180, 136, 137, 147, 191, 137, 147, 191, 148, 136, 133, 191, 134, 140, 129, 135, 191, 65]
result = ""
for i in key:
    result += chr((i - 64) ^ 32)
print(result)
#This_is_the_flag_!

[HNCTF 2022 Week1]Little Endian

enc为

编写脚本（小端序要倒过来一下）

from Crypto.Util.number import *
enc = [0x51670536,0x5E4F102C,0x7E402211,0x7C71094B,0x7C553F1C,0x6F5A3816,]
flag = ""
for i in enc:
    flag += long_to_bytes(i ^ 0x12345678).decode()[::-1]
print(flag, end='')
#NSSCTF{Littl3_Endiannnn}