Teams from 61 countries took part in the CTFZone 2021 ethical hacking competition

Teams from 61 countries took part in the CTFZone 2021 ethical hacking competition

Teams from Russia took 1st and 2nd place, with Italy coming in 3rd
28 June 2021

The CTFZone 2021 international ethical hacking finals were held online on 25-26 June. The training event included the largest attack-defence battle in history, with 334 teams from 61 countries taking part. The event has been hosted since 2016 by BI.ZONE, the expert in strategic management of digital risks.

CTF (Capture the Flag) is a competition that assesses participants’ skills in solving applied cybersecurity tasks: protecting and attacking computer systems, finding and fixing vulnerabilities in services. The key difference between CTFZone 2021 and previous years’ tournaments is the new hybrid format: tasks are presented in jeopardy, attack, defence and security game formats.

Most CTF tournaments are structured as follows:

  • Jeopardy (qualifying stage), hundreds of teams solve problems from a variety of categories;
  • The final, 10 strongest teams meet face-to-face/online in the attack-defence format.

CTFZone 2021 went on for 13 hours and 37 minutes simultaneously in the following three formats:

  • Jeopardy, with 14 tasks from various categories, ranging from professional programming to computer forensics;
  • Attack-defence, where each team was given 3 services, and in order to gain victory points, they had to attack rival services while simultaneously protecting their own resources;
  • Security game, a ‘king of the hill’ type of task which has become a distinctive feature of CTFZone: teams watch in real-time how their own algorithms attack the other teams to see which of them are most efficient.


The remote online format and the scale of attack-defence this year were extremely demanding in terms of the quality of infrastructure. Not only did it have to work flawlessly from anywhere in the world, but it also had to withstand 100 times the load of previous years. This time, 10,000 cores of computing power were used to service the CTFZone. The configuration and support of the non-standard infrastructure was provided by BI.ZONE specialists
Evgeniy Voloshin
Chief Security Officer, BI.ZONE

During the tournament, BI.ZONE provided 24-hour user support: BI.ZONE team used a special online chat to promptly answer questions and monitor the systems’ performance. Despite the increased load on the network, the participants noted the high quality of all infrastructure components and continuous operation of the services.

The prize of $18,000 was shared as follows:

  • 1st place — Bushwhackers, Russia ($10,000);
  • 2nd place — More Smoked Leat Chicken, Russia ($5,000);
  • 3rd place — «httpizza», Italy ($3,000)

Last year’s $18,000 prize pool was divided between teams from Russia and China, who took the top three places in the 24-hour competition. The team from Russia to take first place also won the right to compete in the DEF CON CTF finals, the largest international CTF tournament, which has been held in Las Vegas for more than 30 years.