NNS CTF 2025

Prizes

Prizes and their terms are subject to change prior to the event's start. Terms and conditions apply.

Sponsors

Rules

This document serves as the official rules for the CTF competition. Rules may be clarified or amended by the organizers.

• Do not share solutions, hints, or flags with other teams during the competition.
  • Only challenges that are explicitly in the beginner category allow for educational hints and guidance.
• Do not discuss challenges in public during the competition. Create a ticket on our Discord server if there are any questions.
• Do not attack the CTF infrastructure.
  • Bruteforcing, enumeration, port scanning, and other actions that may result in DoS are strictly prohibited, unless specified otherwise.
  • Service providers are out-of-scope, unless specified otherwise.
• Hints will not be provided in private conversations.
• The participants are responsible for their own hardware and software security. Norske Nøkkelsnikere is not liable for potential damage to your equipment.
• Be nice.

Additional rules apply to community challenge authors during the competition:

• Challenge authors CAN participate in the CTF, but NOT solve their own challenges.
• The challenge author MUST NOT share the idea, solution, flag, or other materials related to the challenge to team members or other players.
• Other members of the challenge author’s team CAN solve the challenge, but MUST NOT first blood the challenge.

Technical Details

The flag format is NNS{[\x20-\x7A]+}.

NNS CTF 2025 is a jeopardy-style CTF. The score per challenge is dynamic and will decay based on the total number of solves.

Participants do not need a VPN to access on-demand/instanced challenges. Challenges will be available via ports 443 (TLS/HTTPS) and 41337 (TLS).

Terms for Prizes

To claim the prizes, we may ask for writeups of the hardest challenges that were solved, and it must be submitted no later than 24 hours after the competition end. Relevant teams will be contacted via the registered email address and/or Discord.

All prizes for NNS CTF 2025 ("The Event") are subject to verification and compliance with local laws and regulations, as well as Norwegian laws and regulations. Norske Nøkkelsnikere ("The Organizers") reserve the right to disqualify, withdraw, or terminate prizes at their sole discretion. Winners must provide sufficient information to confirm eligibility and comply with all applicable laws, including reporting winnings as required. Certain participants may be ineligible due to legal restrictions in their jurisdiction or restrictions set forth by the Norwegian law.

The students category only apply to full-time students enrolled at a Norwegian- school or university. Teams competing in the students category must only consist of students. Each team member must be able to provide proof of their student status. Teams that are eligible for two prizes will need to pick one prize, and the remaining one will be allocated to another eligible team. In such case, teams will be prioritized based on their score and last solve time.

Local Sites

The CTF competition is online, however we provide on-site locations for those who want to meet up. We encourage players to join the physical sites, if possible. Join our Discord server for more information.

Credits

Organizers: Norske Nøkkelsnikere

Local site organizers: Itemize, Datasnok, Helt Sikker, SIFI, BetaSec

Berg CTF platform by NoRelect. Background illustration based on the original work Brudeferd i Hardanger (1848) by Hans Gude and Adolph Tidemand.