RuCTFE is an annual online international challenge in information security. It was held for 4 times already.
The contest is driven by classic rules. Each team gets a virtual machine image containing the set of vulnerable services. Once in a while the jury fills services with private information — the flags. The goal of each team is to find vulnerabilities, fix them on their server and exploit them in order to get flags from other teams. Please refer to the rules page and Wikipedia article for slightly more info.
RuCTFE 2013 starts December 14, 2013 at 10:00 UTC and will last for 9 hours. As usual, the network will be closed for the first hour. The registration opens on November 24 and it will continue until participants number reaches 150.