Capture the Flag (CTF) is a long running tradition at hacker conventions. It pits teams of security researchers against each other on the same network. Every team gets an identical virtual machine image. The VM has a set of custom written services that are known to be vulnerable. The teams work to secure their image while simultaneously exploiting services on the machines of other teams. A scoring server monitors the match as it progresses and awards points to teams for keeping their services up and also for stealing data from their competitors.

The Chaos Communication Congress in Berlin December 27-30, 2008 will host a CTF competition. Most CTF matches are done head to head in the same room. While 25C3 will have local teams, it will also be wide open for international teams to compete remotely. Remote teams will host their own images on a VPN with the other competitors. Now is a good time to register and familiarize yourself with the scoring system. It will certainly be interesting to see how this competition plays out now that teams that can’t make the trip can still compete.