x64_extension

AES-256 密钥扩增魔改

from regadgets import *
k = bytes([0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f,0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f])
iv = bytes([0xff, 0xfe, 0xfd, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8, 0xf7, 0xf6, 0xf5, 0xf4, 0xf3, 0xf2, 0xf1, 0xf0])
a = AES(k)
data = open('flag.txt.enc', 'rb').read()
print(a.decrypt_cbc(data, iv))
# b"Hey Sekai CTF Player, I hope you are fine and are enjoying the CTF. Keep going, here is your reward! The flag is SEKAI{Pl34Se_It'5_jUs7_@_wAaaarmUp}\n"

SEKAI{Pl34Se_It'5_jUs7_@_wAaaarmUp}