Year After Year Link to heading

Swisscom publishes a new Capture The Flag challenge in their security.txt every year. The first puzzle was released in 2022. In December 2023, I learned about it and tried to solve the challenge. Unfortunately, I ran out of time to find the solution¹ within the valid period. I still remember the friendly message² when I eagerly thought I had solved the puzzle:

Your solution isn’t quite right regarding the email address. So I had to take another round internally as well. But you’re generally on the right track – I can tell you that much already.

Keep at it. My colleagues are looking forward to a response with the correct address or answer. 😊

And as background info: we’re already preparing the next puzzle. So it’s worth checking out the security.txt file again in 2024.

Best regards and a puzzling start to the new week. 😊

Then, unfortunately, I didn’t find the time to tackle the 2024 challenge. Work commitments and other projects took priority, so I decided to defer my CTF participation. I turned my attention to the 2025 edition instead, hoping for a fresh start. But that one also remained unsolved - another year slipped away without crossing the finish line.

2026 Link to heading

However, I was determined to break this streak in 2026. After two consecutive years of missed opportunities, I committed to tackling the puzzle early and dedicating the necessary time to see it through. What followed was a weekend journey filled with learnings, persistence, and finally - a flag to submit.

Within days of my submission, I received this confirmation:

Since the challenge is still ongoing, I prefer not to write about it in detail. I might publish a detailed writeup once the year is over. However, if you’re interested in solving this challenge or previous years’ puzzles, feel free to check out the GitHub Repository from Swisscom.³ You can replay everything there.

With that in mind, I’d like to leave you with a short farewell video⁴: