题目很简单:
tata mb xwhvxw mlnX sTRtI4JNqEfuaa7LnT5MyJVA046GnTRt54Twg9UAd4JtyXLNUF6E :xkxa lb ztey xaH
随便搜索了一下,找到2019年的类似题目:
Crypto CTF 2019 - Decode Me!
https://ctftime.org/writeup/16108
利用相同的脚本,直接把内容换一下,即可得到flag:
cipher = "tata mb xwhvxw mlnX sTRtI4JNqEfuaa7LnT5MyJVA046GnTRt54Twg9UAd4JtyXLNUF6E :xkxa lb ztey xaH"
cipher = cipher[::-1]
print(cipher)
decoded_cipher = ""
for i in range(len(cipher)):
if cipher[i].isupper():
val = ord(cipher[i]) + 12
if val > ord('Z'):
val = (val - ord('Z')) + ord('A') - 1
decoded_cipher += chr(val)
elif cipher[i].islower():
val = ord(cipher[i]) + 7
if val > ord('z'):
val = (val - ord('z')) + ord('a') - 1
decoded_cipher += chr(val)
elif cipher[i].isdigit():
val = ord('0') + ((int(cipher[i])+25) % 10)
decoded_cipher += chr(val)
else:
decoded_cipher += cipher[i]
print(decoded_cipher)
import base64
print(base64.b64decode(decoded_cipher[len("The flag is here: "):len(decoded_cipher)-len(" Just decode it haha")]).decode())
flag:
CTFer_i_d0n't_th1nK_y0u_cAn_hand1e_Th1s