| Embedded Security CTF | https://microcorruption.com |
| EnigmaGroup | http://www.enigmagroup.org/ |
| Escape | http://escape.alf.nu/ |
| Google Gruyere | http://google-gruyere.appspot.com/ |
| Gh0st Lab | http://www.gh0st.net/ |
| Hack This Site | http://www.hackthissite.org/ |
| HackThis | http://www.hackthis.co.uk/ |
| HackQuest | http://www.hackquest.com/ |
| Hack.me | https://hack.me |
| Hacking-Lab | https://www.hacking-lab.com |
| Hacker Challenge | http://www.dareyourmind.net/ |
| Hacker Test | http://www.hackertest.net/ |
| hACME Game | http://www.hacmegame.org/ |
| Halls Of Valhalla | http://halls-of-valhalla.org/beta/challenges |
| Hax.Tor | http://hax.tor.hu/ |
| OverTheWire | http://www.overthewire.org/wargames/ |
| PentestIT | http://www.pentestit.ru/en/ |
| CSC Play on Demand | https://pod.cybersecuritychallenge.org.uk/ |
| pwn0 | https://pwn0.com/home.php |
| RootContest | http://rootcontest.com/ |
| Root Me | http://www.root-me.org/?lang=en |
| Security Treasure Hunt | http://www.securitytreasurehunt.com/ |
| Smash The Stack | http://www.smashthestack.org/ |
| SQLZoo | http://sqlzoo.net/hack/ |
| TheBlackSheep and Erik | http://www.bright-shadows.net/ |
| ThisIsLegal | http://thisislegal.com/ |
| Try2Hack | http://www.try2hack.nl/ |
| WabLab | http://www.wablab.com/hackme |
| XSS: Can You XSS This? | http://canyouxssthis.com/HTMLSanitizer/ |
| XSS Game | https://xss-game.appspot.com/ |
| XSS: ProgPHP | http://xss.progphp.com/ |