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tl;dr To give the emerging COVID-19 pandemic situation some time to become the long-term stable COVID-19 pandemic, the OOO is delaying quals to the weekend of May 16th.

Everyone reading this is heavily impacted by COVID-19. Some countries, in which the breakout occurred early, have hunkered down and adjusted, with hackers in those countries now very well used to isolating at home. Other countries, in which the breakout is actively emerging, are experiencing relatively high amounts of chaos as new lockdown measures come into effect and people must adapt. One specific example of the latter is some US universities are shutting down dorms and students are scrambling to find somewhere to live next week. Another one is the wave of shutdowns currently facing European countries as the virus spreads there as well.

Hackers in this situation are frantically ensuring access to supplies, determining new work environments, and trying to adapt to a new way of life. What many cannot prioritize at this time is CTF, even if it is DEF CON CTF Quals.

When we were players, DEF CON CTF was, for us, the highlight of the hacking year. It was not a secondary thought during a desperate time of adjustment, nor a convenient distraction to pass the time during lockdown. Now, as organizers, we strive for the teams playing our game to have a DEF CON experience as meaningful as our experiences were. With that goal in mind, we are pushing DEF CON CTF Quals back by about two months, to 48 hours starting from May 16 00:00 UTC.

In two months, COVID-19 won’t go away. We will likely all still be in isolation, and travel will still likely be restricted. What it will do, however, based on its progression curve in the early-impacted countries, is “stabilize”. Hopefully, in two months, the world will not be experiencing scary new COVID-19-driven changes on a daily basis, will not be scrambling for daily necessities and housing, and will be settled into the new medium-term reality of working from home, collaborating over video, and so on. And then, right as things start getting really old, DEF CON Qualifiers can be there for everyone to focus on!

The CTF community is a sea of free thinkers and, doubtless, everyone will have their own take on this scheduling change. We know that many of you make plans to meet in person for DEF CON CTF Quals, and that this announcement will derail the plans that COVID-19 hadn’t already wiped out. This is something that we considered and agonized over, but in the end, we feel that this is the right move for the community as a whole. We ask that you be understanding that, even though your position might be stable, that is not the case for everyone. Please bear with us as we try our best to provide a workable DEF CON CTF Quals timing for everyone!

Some expected-to-be-FAQs:

What about DEF CON Finals?

DEF CON is watching the situation carefully. Their update is here, but the tl;dr is that we’ll know more on June 1st.

Do you expect the pandemic to go away in two months?

To reiterate, we don’t expect COVID-19 not to be a problem in two months. But right now, it’s an actively developing problem, and one that people need to respond to without being distracted by quals. We want everyone to be able to give it their all in the CTF, rather than worrying about toilet paper!

Isn’t May 16th a bit late?

The new date is actually more in line with prior years: 2019’s quals were on May 11th, and 2018’s were May 12th. This year, we had intended to give more time between quals and finals to make planning easier for the teams and for us, but we feel that giving the current situation time to stabilize is more important.

Qualifying to DEF CON CTF 2020

Register now:

Quals Countdown:

Everyone will have a chance to qualify through our online event.

Plan for 2 days, starting from May 16th UTC (CTFtime - timeanddate)

Start practicing now, either by solving our old challenges or by playing in awesome CTFs.


Only the world’s top teams make it to DEF CON. This enables the event to explore the cutting edge of the amazing things that the world’s hackers are capable of. But the trick, of course, is figuring out who these hackers are. In CTF, this is done through cut-throat competition.

Every year, the DEF CON CTF organizers select a number of prominent events in the CTF community as prequalifiers. The winner of each of these is automatically invited by the Order of the Overflow to compete in DEF CON CTF, and the OOO completes the roster by selecting teams through our own qualification round (scheduled this year for March 27th!) as well as last year’s DEF CON champion.

We select pre-qualifying events according to several considerations. We always look for quality events that present a variety of interesting challenges to their participants. We look for both prominent events with an established history and promising up-and-comers. And we have an additional metric: connecting the various global hacker communities. We want qualifiers not only to represent quality and innovation, but also to enable DEF CON to be a place where top hackers from the different worldwide hacker communities come together!

To that end, the Order of the Overflow has selected the following events as pre-qualifiers:

Additionally, teams will prequalify through the following DEF CON events:

From these events, we will identify the top hackers in the CTF community, invite them to DEF CON, and watch them battle it out at DEF CON 28. See you there!