The Country-to-Country CTF (C2C) Cybersecurity Challenge is a series of international CTF competitions organized by the International Cyber Security – Center of Excellence (INCS-CoE) with leading international universities. The 2026 competition is hosted by Universitas Indonesia.

C2C is an exciting opportunity for students to work together as international teams to solve interesting CTF challenges, learn new skills, socialize, and promote international collaboration and friendship. Interested university students across Japan, Singapore, Indonesia, or any one of the countries that are a part (party or signatory) of the Budapest Convention can participate in the qualifying competition on February 6 – 7, 2026.

The final round of team competition will be held at Universitas Indonesia, Bali, on August 10 – 14, 2026

The Country-to-Country CTF (C2C) is an annual global Capture-the-Flag competition that promotes international collaboration in cybersecurity.

Organized by the International Cyber Security – Center of Excellence (INCS-CoE), C2C brings together students from across partner universities to learn, compete, and innovate in a spirit of friendship and cooperation.

The 2026 event will be hosted by Universitas Indonesia in Bali, continuing the legacy of previous C2C-CTF editions held in Japan, the United States, the United Kingdom, and Australia.