Security Challenge by Hellenic Cyber Security Team

kindly offered byHellenic Cyber Security Team, University of Piraeus and Sealed Grid

Date / Time: Friday 2 December / 15:10-16:30 EET

Speaker: Christos Xenakis
Professor @ University Piraeus

Speaker: Michalis Takaronis
Associate Researcher @ University Piraeus

Speaker: Athanasios Vasileios Grammatopoulos
CyberSecurity Researcher @ University Piraeus

Challenge Description 

In this short Capture the Flag (CTF) competition you will be asked to compete against each other in solving four security related challenges in about one hour. To solve a challenge, you may have to analyse digital files, reverse engineer binaries, crack hashes, break cryptographic algorithms or exploit programs’ vulnerabilities.
Three of the challenges will be offline and one will be online. For the offline challenges, you will have to download the challenges’ files and analyse them locally on your computer to recover the embedded flags. For the online challenge, you will be given access to a vulnerable service which you will have to hack and recover the hidden flag.
During the competition the CTF organisers may change the pool of available challenges if any problem occurs (e.g. network problems) in order to keep the competition running.

Get ready, setup your Linux VMs, install your network analysers, fire up your reverse engineering tools and don’t forget to bring your exploitation cheat sheets. But remember… do not share flags, do not attack machines that are not part of the competition, do not attack the competition infrastructure, you may brute force only offline challenges, and of course have fun!

What will you Learn: 
– Learn more about Capture The Flag (CTF) competitions and their alternative gamified approach for delivering cybersecurity training.
– Experience a beginner’s level Capture The Flag (CTF) competition.
– Introduce yourself into ethical hacking.

Level: Beginner / intermediate

Target audience: People with basic hacking skills that wish to take a Security challenge

Prerequisites on Audience: 

  • (recommended) Linux distribution installed (as host OS or VM)
  • Basic knowledge of cryptography, forensics and web exploitation.
  • Basic Knowledge of specific tools like image manipulation tools, decompiler (ghidra, ida), packet analyzers(wireshark, brim, etc).

– Top contestants will be invited to Hellenic Cyber Security Team’s private discord server.


  • Organize the participants and set up their laptop
  • Short presentation / instructions to the contestants. The purpose of the presentation is to explain the competition structure to beginners and present the challenges.
  • Give access to the competition platform. Contestants will then be able to download challenge files and access online services. The status of the competition will be displayed live through a scoreboard.
  • During the competition the support team will help the contestants resolve any issue that may occur.