ZeroDays CTF 2025

ZeroDays is Ireland's largest CTF. Running since 2015, it has grown to be the largest on-site, one-day CTF in the world. In 2024 over 130 teams of four competed with over 500 competitors in total. The event has three categories for Irish colleges, International teams and an Open section for any team to enter.

International competitors welcome. Expect a wide range of challenges suitable for all skill levels; plenty of easy challenges for newer players and some extremely difficult challenges for more experienced players.

International teams can purchase a ticket here: https://www.eventbrite.ie/e/zerodays-ctf-2025-10th-anniversary-tickets-1130688773559

The CTF will take place in Croke Park on the 22nd of March. For more details see our website.