Online challenges
Live
- Archives (Defcon CTF, GItS, Hack.lu, NDH, ...) http://capture.thefl.ag/
- Hack.lu
- rwthCTF 2011
- https://wiki.mozilla.org/Security/Events/CTF
- Ghost in the Shellcode
- http://ctf.forbiddenbits.net/?
- Plaid CTF 2012
- Defcon CTF
- ...
Permanent
- http://www.newbiecontest.org
- http://www.hackthissite.com
- http://hackbbs.org
- http://www.try2hack.nl
- http://www.overthewire.org
- http://www.root-me.org/fr/Capture-The-Flag/
- http://p0wnlabs.com/free/vms
- https://www.hacking-lab.com/
- http://honeynet.org/node/828
- http://exploit-exercises.com/
- https://stripe-ctf.com
- ...
IRL challenges
- Insomni'Hack
- Jurackerfest
- ...