Natjam on 12:03 AM 12/15/2024: Thanks for the macOS crackmes, they are really needed, keep going!
Natjam on 1:11 PM 12/15/2024: Serial for name: natjamxd is KRACK-2368128FBC
Matimuu on 2:37 AM 12/25/2024: Nice puzzle
matimuu
KRACK-8F592EFFBC
lylythechosenone on 4:28 AM 02/06/2025: The Objective-C almost killed me. Nice challenge.
Coder_90 on 11:55 AM 10/12/2025: For name = “Coder”
MD5("Coder") (UTF-8, uppercase hex) = 14C0F98E06BCD735D89C0C6A57488CCD
First 7 hex chars = 14C0F98
Therefore, any valid serial for “Coder” must be:
FBC
KRACK-14C0F98FBC :)
Coder_90 on 12:26 PM 10/12/2025: import hashlib
import string
def md5_hex_upper(s: str) - str:
return hashlib.md5(s.encode("utf-8")).hexdigest().upper()
def build_serial(name: str, prefix6: str) - str:
if len(prefix6) != 6 or any(ch not in string.printable[:-6] for ch in prefix6):
raise ValueError("prefix6 must be exactly 6 printable ASCII chars")
mid7 = md5_hex_upper(name)[:7]
return prefix6 + mid7 + "FBC"
if __name__ == "__main__":
name = input("Enter name: ").strip()
prefix = "KRACK-"
try:
serial = build_serial(name, prefix)
print("Your Serial is:", serial)
except ValueError as e:
print("Error:", e)
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