LakeCTF is a jeopardy-style security hacking contest organized by the polygl0ts CTF team (plus some friends!) and the EPFL School of Computer and Communication Sciences (IC).

Participants first compete in an online qualification round, and the qualified teams will physically compete in the finals in Lausanne. The top teams will have the unique chance to meet the top members of the EPFL research community.

We wish you the best of luck !

Quals schedule

Qualification start Sat 4th of November, 18:00 UTC
Qualification end Sun 5th of November, 18:00 UTC

Finals schedule

Thu 2nd of May 2024 Arrival
Apéro with polygl0ts and members of the EPFL community
Fri 3rd of May 2024 9:00 CTF Finals Start
17:00 End and Award ceremony

Coincidentally, Balélec (Europe's biggest student-run festival) takes place on the EPFL campus on Friday evening. Keep this in mind for potentially celebrating your victory (or getting over your loss)!

Travel and accomodation

Accomodation during the finals (i.e., from Thu 2nd of May to Sat 4th of May 2024) will be gratiously provided by EPFL's IC school. Thanks to our sponsors, we are also able to reimburse up to 1000CHF per team for transportation to Lausanne for this year's finals!


CTF Finals INM 065 at EPFL
Hotels TBD


  • There is no limit on the number of people who may participate in a single team in the quals.
  • Up to 10 teams will be invited to the finals (8 academic teams; 2 non-academic teams). The finals will take place physically in Lausanne at EPFL. Only 8 players per team will be allowed to play the finals. Remote players are not allowed.
  • 7 out of the 8 academic teams for the finals will qualify through LakeCTF quals. The last team invited to the finals will qualify through Insomni'hack CTF taking place the week before. This team will be the highest-ranking team from Insomni'hack's academic bracket that has not qualified via LakeCTF quals already.
  • A team can only participate as an academic team if, at the time of the qualifications, every team member is a member of an academic institution (high schools, colleges/universities). Switching from/to academic/non-academic team status after the start of the qualifications is not allowed.
  • Sharing flags or solutions during the contest is strictly prohibited. This action is subject to disqualification.
  • Attacking machines other than those designated as LakeCTF 2023 target machines is prohibited.
  • If you find a bug in the contest infrastructure, congratulations (but you should report it).
  • EPFL students/staff can take part in the quals but are not allowed to qualify for the finals.
  • If you are not sure if something is a violation of the rules, it probably is.


  • Our primary method of communication for the CTF will be the official competition Discord.


All teams that qualify for the finals will have accommodation during the CTF (Thu - Sat) paid by EPFL. The top team from the quals will receive 8 tickets for the Insomni'hack Cybersecurity conference taking place the week before the finals. The tickets are sponsored by Orange Cyberdefense Switzerland.

Top 3 teams in the finals will receive the following prizes:

🥇 First place 1 Life sized psyduck plushie + 8 Led shoes
🥈 Second place 8 POC||GTFO books and 8 blinkenrocket kits
🥉 Third place 8 Amazon Gift cards and 8 Arch linux live CD-ROM

All players from the top three teams will also receive a challenge coin each.


LakeCTF's first edition took place on the special occasion of the 20 years anniversary of the IC School (Computer and Communication Sciences) in 2022. Due to its great success, we are organizing the second edition of LakeCTF with online qualifiers in fall 2023 and finals on EPFL's campus in Lausanne in spring 2024.

polygl0ts is the official EPFL CTF team. It was born in 2018 and is still going strong, taking part in major CTFs as part of the bigger organizers team, one of the top teams on CTFtime. It's also a commission of CLIC, the computer science student's association at EPFL.


BBS logo
Unlock your Cybersecurity Career at BUG BOUNTY SWITZERLAND

Calling all brilliant minds and aspiring cyber warriors!

As the Swiss market leader for Bug Bounty Programs and Public Trust Initiatives, we set new standards in cybersecurity and collaboration. We are working on an important mission: a secure digital Switzerland.
To achieve this mission, we recognize that exceptional talent is the backbone of our success. Whether you are a seasoned ethical hacker, a cybersecurity researcher, or just starting your journey, we offer diverse career paths that cater to your unique skills and interests. Together, we establish a new standard for cybersecurity in Switzerland.
We are looking forward to having great conversations and sharing valuable insights with you throughout the hacking contest. If you are ready to embark on this thrilling journey and become a cybersecurity hero, we invite you to join us in the fight against cyber threats, and together, we will build a safer digital world.

Infomaniak logo

Infomaniak's mission is to develop technological independence in Europe with ethical cloud solutions that make no compromises on ecology and privacy. Committed to privacy, the local economy and ecology, Infomaniak is a Swiss cloud provider that develops a suite of online collaborative tools and solutions for cloud hosting, streaming, marketing and events. The company uses exclusively local renewable energy, builds its own data centers and develops its solutions in Switzerland, without relocating. It was awarded the Prix Suisse de l'Ethique 2023 and the Prix du développement durable 2023 by the canton of Geneva for its new data center, which will fully recycle the energy it consumes to heat up to 6,000 households.

Orange Cyberdefense logo

Orange Cyberdefense is the expert cybersecurity business unit of the Orange Group, providing consulting, solutions and services to organizations around the globe. We believe strongly that technology alone is not a solution. We help our customers achieve superior security outcomes via our 3000+ security professionals, partnerships with top-tier vendors, threat intelligence and in-house R&D including a CERT and Epidemiology Lab.
Orange Cyberdefense Switzerland is born from the acquisition in 2022 of SCRT and Telsys: two long-standing players in the Swiss cybersecurity landscape. By combining the expertise of the Swiss-based team (120+ people) with the support of the broader Orange Cyberdefense group, we can offer a global protection combined with local expertise and support to our Swiss-based customers.
Orange Cyberdefense Switzerland (previously SCRT) are also the founders and organizers of the Insomni’hack cybersecurity conference and hacking contest, which grew from a small CTF in 2008 to a major cybersecurity event in Europe nowadays.