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CTF & training

Registering and submitting flags on the CTF

The CTF (ctf.cyber-guardians.co.uk) is a separate, self-contained platform from the client portal — it uses its own username and password, not your portal login. Challenges are attempted directly against training.cyber-guardians.co.uk (the isolated Juice Shop instance), and the flag you find there is submitted back on the CTF platform to score points.

Troubleshooting guideReviewed

Steps

Work through these in order.

  1. 01

    Register a CTF account first

    Visit ctf.cyber-guardians.co.uk and register with any username and password — no email verification step, so you can start immediately.

  2. 02

    Attack the target, not the scoreboard

    Challenges are solved against training.cyber-guardians.co.uk. The CTF platform itself has no vulnerabilities to find — it only tracks and scores the flags you submit.

  3. 03

    Copy flags exactly

    Flags are case-sensitive hex strings. A flag that looks right but isn’t accepted usually has a stray trailing space or a missed character from a copy-paste — retype it manually if in doubt.

  4. 04

    Remember the target resets nightly

    training.cyber-guardians.co.uk resets every night at 03:00 UTC. Any state you’ve built up mid-challenge (e.g. a logged-in session, uploaded files) will be gone after a reset — this is intentional and doesn’t affect flags already submitted.

Not resolved?

Get in touch directly.

Stuck on a specific challenge is normal — that’s the format. If something looks actually broken (the target is unreachable, the CTF platform itself errors out), let us know and we’ll check the infrastructure.

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