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.

Keep your eyes peeled for DEF CON’s Call for CTF Organizers.

Organizing the Future

Interested in organizing DEF CON CTF in the future? Here are some resources that should help:

• OOO’s DEF CON CFO proposal submission
• LegitBS’s experience submitting and hosting

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 team@oooverflow.io.

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

Public Sources

github/o-o-overflow

Archive

We launched a playable archive of our past challenges: archive.ooo (info)

We owe thanks to many people -- some are listed here