ogmini - Exploration of DFIR
Having fun while learning about and pivoting into the world of DFIR.
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Magnet Virtual Summit 2025 CTF - AAR "The masked singer"
by ogmini
A child could solve it?!
During the actual competition, I intentionally ignored all the cipher questions. I just wasn’t confident in my ability and felt I would be wasting my time. This one ended up being a fun challenge for a unique reason I’ll get into below.
Continuing with my writeups on my “fails” or the ones I just couldn’t figure out in the timeframe alloted. I want to talk about how I went about trying to solve the challenge and where I went wrong. This should help me in the future by highlighting weaknesses and areas for improvement. Each post will focus on just one “fail” challenge. You can find all my writeups here.
The masked singer
Title: The masked singer
Description: Who is the singer?
This challenge was under the Cipher section and worth 10 points. It was the second challenge in the category.
My Process
- Provided a zip file with 16 images that are obviously pieces of a QR Code. The finder patterns are very evident.
- I could just manipulate these in an image editor and recreate the image.
- No! Let’s print these out, cut them out, and have my kids solve a puzzle.
- Benefit, give them something to do and exercise their mind.
Actual Solution
It took me forever to cut the pieces out with normal scissors. I should have used a craft knife. Handed the pieces to my kids and gave them instructions to put the puzzle together. The youngest as a normal 3 year old quickly got bored and wandered off. The oldest who is in 1st grade finished the puzzle in about 10 minutes with some complaints about my quality of cutting accuracy. I promptly scanned the QR Code with my phone and got rickrolled for my troubles. The oldest had no idea about rickrolling, was rather miffed about the payout, and didn’t care to listen to my explanation.
Lessons Learned
- I need a laser cutter to quickly cut puzzle pieces.
- The new generation doesn’t know about rickrolling.
- Figure out how to involve the kids more in some age appropriate fashion.
- Seriously though, next time I’ll at least take a quick look at cipher challenges.