3137.mp4

Did you find the flag by running strings 3137.mp4 | grep "CTF{" ? 4. Final Flag Flag: FLAGexample_flag_123

A quick summary of the trick (e.g., "The flag was hidden in the LSB of the audio channel"). 3137.mp4

Briefly state what the goal was (e.g., "Find the hidden flag within the video file"). Did you find the flag by running strings 3137

List your toolkit, such as ExifTool , FFmpeg , StegSolve , Sonic Visualizer , or Strings . 2. Initial Analysis Describe your first steps after receiving the file: Briefly state what the goal was (e

This is the core of your write-up. Explain the "Aha!" moment:

If you found something in a single frame, explain how you extracted it using ffmpeg -i 3137.mp4 -vf "select=eq(n\,3137)" -vframes 1 out.png .

If the video looked normal, did you check the audio track? Mention if you used Audacity or Sonic Visualizer to look at the Spectrogram for hidden text.