Welcome, hackers of all ages.
It was an honor to play with you in these four years. We hope our successors will be as lucky.
Organizing the Future
DEF CON’s call for the new CTF organizers is out!
Interested in organizing DEF CON CTF in the future? Here are some resources that should help:
We’d be happy to help with proposals and the transition if useful!
Who are we?
We are the Order of the Overflow. We
are were the host of DEF CON CTF (Quals
and Finals). Read about us and our philosophy here or reach us at
We’re still on Twitter as @oooverflow!
DEF CON CTFs
- DEF CON CTF 2021 Finals
- DEF CON CTF 2021 Quals
- DEF CON CTF 2020 Finals
- DEF CON CTF 2020 Quals
- DEF CON CTF 2019 Finals
- DEF CON CTF 2019 Quals
- DEF CON CTF 2018 Finals
- DEF CON CTF 2018 Quals
We launched a playable archive of our past challenges: archive.ooo (info)
We owe thanks to many people -- some are listed here