For teachers · Redline-CTF
What an event day looks like
You run the class; we run the range. Here's who does what, from the day before to the results afterwards.
00
The day before
Line Zero
We deploy your range and run the full health check on the scoreboard, the desktop gateway, student isolation and every challenge.
You
Share the scoreboard link with your students. Tell us your end time and lab hours if you haven't already.
01
Students log in
Line Zero
Each new account is given its own lab automatically, so there's no roster to upload.
You
Students register with any username and a password. No email address or real name needed. Then they click Open Kali and a desktop opens in a new tab.
02
During the event
Line Zero
We're on call remotely, and based in Arizona. If a student breaks their lab, we rebuild it from a clean state and their score is kept.
You
Watch live scores and activity from your instructor dashboard, and step in where students are stuck.
03
When it ends
Line Zero
Flag submissions close at your end time. Once you have your results, we tear the whole range down, scoreboard database included.
You
Download every solve and point adjustment, and grade any written work.
Your instructor dashboard
A login on the scoreboard just for teachers, at /admin.
- Live scores and activity
- The scoreboard refreshes on its own as flags come in, and the dashboard logs admin actions and failed logins.
- Student accounts
- See every student, disable a login, clear a lockout, or remove an account to free its lab for someone new.
- Points with a reason
- Award or deduct points, with a note, for written work or anything the flags don't capture.
- Challenges on and off
- Hide a challenge mid-event, and it disappears from the student catalog and stops taking flags.
- Co-teacher logins
- Give each co-teacher or aide a named instructor account instead of sharing one password.
- Results export
- Download every solve and manual point adjustment as a JSON file.
Built so the scores mean something
- Every flag is unique to the student who found it, so a classmate's flag won't work.
- Hints are on the scoreboard and cost 10% of a challenge's points each, up to 50%.
- Teams share hints and their cost, and each member still finds their own flags.
- Flag submissions are rate-limited, so guessing doesn't pay.
- Rules of engagement are on every desktop, and each student's network is walled off from everyone else's.
Questions teachers ask
Do students need to install anything?
No. The Kali Linux desktop runs in a browser tab: no VPN, no SSH client and no virtual machines to set up. Any laptop or desktop with a modern web browser works, including school Chromebooks.
What does our school network need to allow?
Ordinary HTTPS (port 443) to the range. If your district filters web traffic, we can send your IT team the hostnames to allow ahead of time.
What information do students give when they register?
A username and a password of their choosing (8 characters or more). We don't ask for an email address or a real name, so students can use a callsign.
Is it safe to have students attacking things?
Every student attacks only their own private lab. No two students share a network, and the vulnerable targets have no public IP addresses, so they can't be reached from the internet.
What if a student breaks their lab?
Many services recover on their own within a minute or two. If not, we rebuild that student's lab from a clean state during the event. Their score is kept, but anything saved on the desktop is lost, so students should keep notes outside the lab.
Can the range run across several class days?
Yes. On a daily schedule the lab shuts down after class and comes back as it was. Students see a warning banner up to an hour before each shutdown.
Can students work in teams?
Yes. Students create a team on the scoreboard and invite classmates. A team's score is the sum of its members' scores.
Do teachers get the solutions?
Yes. Your instructor guide includes a walkthrough for every challenge, so you can unblock a stuck student without solving it for them. Students never see the walkthroughs.
How is work graded?
Flags are scored automatically. A few challenges also ask for a written report or narrative, which you can grade yourself and add to a student's score from the dashboard.
Planning a CTF day or competition season?
The first 5 schools save 25% on any plan for their first 12 months. Offer ends June 30, 2027.