News and events archive

The Slovak Cyber Team won the ZeroDays CTF, a prestigious student competition held on 23 March 2025 in Dublin, Ireland. Two students of the Faculty of Informatics of Masaryk University, Marek Geleta and Ivan Lepieš, also contributed to its success.

Success in international competition

The ZeroDays CTF competition has a ten-year tradition in Ireland and this year, for the first time, it was also open to international participation. The competition was extremely strong - a total of 119 teams from different countries took part. Capture the Flag (CTF) is a type of cybersecurity competition where participants search for so-called flags – special text codes hidden in a system, file or application. They earn these "flags" by exposing and exploiting security weaknesses. Each flag earns points and the team with the highest score wins.

Contestants tackled challenges in web security, reverse engineering, digital forensics, cryptography, hardware hacking and other disciplines. Teams of four hacked digital services and physical devices. Slovakia was represented in Dublin by Marek Geleta, Ivan Lepieš, Tomáš Proks and Matúš Mandzák. The first two are students of the bachelor's programme in Cybersecurity at FI MU.

A well-matched team – who will join?

The Slovak Cyber Team managed to win thanks to a well-planned team division of tasks and effective cooperation. "The most difficult part was to solve tasks under time pressure and to divide the work effectively," said Ivan Lepieš. "However, we managed to get several 'First Bloods' - that is, to solve the tasks first - and even managed to solve some tasks as the only ones in the whole competition."

For Mark Geleta, the team captain, cryptography was the most difficult area, in which the team is still looking for new reinforcements. "We are actively looking for a cryptographic wizard to join the team, but we have not yet succeeded," he explains. The team selects new members mainly from the CyberGame competition, which is currently underway for this year, but also from other competitions. In addition, they plan to post a set of challenges on www.cyberteam.sk which will also serve as a recruitment tool for the team.

Studies that further develop talents

Marek and Ivan made it to the national team thanks to their results in the Slovak CyberGame competition. They have been involved in cybersecurity since they were high school students. As part of their studies at FI, they are now broadening their horizons in the field. For example, Marek Geleta's knowledge of low-level programming has led him to reverse engineering and binary exploitations, or to hardware hacking and side-channel attacks. "My bachelor's thesis, in which I design a task generator for CTF competitions and security training, is also advancing my skills. It gives me a better understanding of how things work, and the perspective of a task author helps me in solving tasks as well," he adds.

Ivan Lepieš considers his development in cryptography to be the most useful, as well as the new experience he can use not only in competitions but also in practice.

"I'm glad that half of the successful team is studying cybersecurity at FI, because the team members can motivate our students to participate in similar competitions, such as the Cybersecurity Competition and the European Cybersecurity Challenge. The most successful teams are the ones that not only have advanced technical skills, but are also well-coordinated," explains Assoc. prof. Jan Vykopal, guarantor of the bachelor's degree programme in Cybersecurity at FI MU.

Preparing for the European finals

Students now face another challenge - participation in the prestigious European Cyber Security Challenge 2025, which will take place in Warsaw. This competition is the official European Cyber Security Championship and is organised by the European Union Agency for Cybersecurity (ENISA). Preparation includes intensive training, online CTF competitions and bootcamps organised by the Cybersecurity Competence and Certification Centre. "My big dream as a team captain is to make the top 10, but we will have to really work for it," says Geleta.

We congratulate the students on their outstanding achievement and wish them the best of luck in future competitions!

For more information about the team's success at ZeroDays CTF, please read the press release from the Slovak Cybersecurity Competence and Certification Centre.

For more information on the Czech Cyber Security Competition, please visit https://www.kybersoutez.cz/, and for the Slovak CyberGame, please visit https://cybergame.sk/. At FI we also organise the annual Cybersecurity Summer School, where we select the Czech national team for the European Cybersecurity Challenge among the finalists of the Czech Cyber Security Competition. The Czech and Slovak teams will compete against representatives from European countries.

Author: Marta Vrlová, Office for External Relations and Partnerships at FI MU

Photo: Slovak Cybersecurity Competence and Certification Centre & Marek Geleta