Hi im doing one ctf its reverse chalenge can you ...
Created on: August 28, 2026
Answered using GPT-5.6 Thinking by Chat01
Question
challenge3.exe
Hi im doing one ctf its reverse chalenge can you solve this for me Analyze the fiile challenge3.exe and determine the hexadecimal value used as the divisor in its final checksum validation on the machine with the IP address 172.25.65.103.(Answer Format: NxNX)
Reverse engineer challenge3.exe on the target machine with the IP address 172.25.65.103 and identify the standard algorithm implemented by the membership validation function.(Answer Format: Xxxx Xxxxxxxxx) do little quick
Thought
Answer
- Final checksum divisor (hex):
0x0A - Membership validation algorithm:
Luhn Algorithm
The validation routine doubles alternating digits, subtracts 9 when needed, sums them, then checks sum mod 10 == 0 — standard Luhn.