Solving a CTF Challenge: Decoding the Secret Message

In this blog post, I will walk you through the steps I took to solve a Capture the Flag (CTF) challenge, where the goal was to decode a hidden message. Below, you'll find a detailed explanation of my process along with screenshots to illustrate each step.

Challenge File

Step 1: Analyzing the Packet Capture

The first step was to examine the packet capture file (shark1.pcapng) using Wireshark. By following the TCP stream for stream 5, I was able to isolate the relevant HTTP traffic.

In the stream, I found the following encoded message: