When an attack is detected on a web server, some defenders try to handle that incident, by getting rid of the intruders and by hardening their infrastructure so that they won't be owned again. Sometimes they get enough spare time to analyze what happened exactly, by doing some kind of forensics actions, or by contacting remote administrators and authorities, etc. But recently, attackers might not really be afraid of the consequences of their digital crimes.This talk proposes to think further and to re-balance the Internet war between the light side and the dark side. We will add a new way to behave when evil hackers are caught on a host. Indeed, TEHTRI-Security will explain how to strike back against your web assailants, so that you would be able to: get more information about them or identify them, steal their tools and methods, or sometimes to penetrate back their own computers too. Of course those technical initiatives might lead to legal issues, depending of the international and local laws (self defense, etc). But this talk will focus on tactical issues, to show real life examples when it might be possible to hack the web hackers.