NUS Greyhats qualified for LakeCTF 2022 during the recess week. We got to go to EPFL, Switzerland for the finals!


The qualifiers itself was a very thrilling experience. We solved three challenges in the last hour of the CTF – including a challenge that I spent ~18 hours on. I even dropped a module because I didn’t have time to study for the midterm ^~^ (Monday midterms are a tragedy).

Day 1

After a ~13 hour set of flights, we arrived at Geneva. We took a train to Lausanne and checked into our hotel.

The organizers fetched us from the hotel and gave us a tour of EPFL.

Day 2

It was Competition Day! I actually woke up around ~2am since I had to participate in another competition. Nevertheless, after we ate a hearty breakfast, we arrived 5 minutes late. The competition itself was amazing – I did not expect an overseas CTF of this level to be like this. I managed to first-solve both of the binary exploitation challenges – writeups for one of them are here.

We had dinner with the organizers afterwards, where we mingled with other teams. I met up with the challenge author who was surprised (and frustrated) that I solved the challenge the wrong way 🙂

Day 3

After some walking, we ate breakfast:

We also ate some Cheese Fondue.

Day 4

We travelled to various parts of Lausanne:

We walked all the way down to the docks of the lake to get some scenic pictures:

These images are my Desktop wallpaper right now.

Day 5

We travelled to Geneva so that we could visit some places before our flight:


In my opinion, the CTF and travel experience were wonderful. Life in Switzerland felt a lot slower and more relaxing compared to Singapore (though the Cost of Living is a bit high).

I would like to thank the NUS School of Computing for SToW as well as my teammates in NUS Greyhats for making this trip and qualification possible.