ExploitHub.com will be a web store allowing IT managers to purchase vulnerability testing applications to see if any of their networks or websites can be exploited by hacker exploits. The company producing this website is a security company with a very good standing in the U.S. corporate world, but this particular identity is brand new.
The target audience is IT managers and systems administrators and possibly web developers. It will be important to NOT look like a hacking site, and to convey a professional, corporate identity. But the target can also be pretty interesting characters themselves, and definitely are sophisticate web users, so the logo should not be boring, and should convey the sophistication of the people behind exploit hub as well.
The logo will be used on a white background. I don't have any ideas for icons or marks that might represent "exploits", but anything that would represent security testing, fortifying, immunizing, strengthening or preparing would probably do well. It could be that the best logo doesn't really have a significant mark at all - just like the website for rapid7.com, which is affiliated with the people developing this new website (they are not directly involved with it though). The logo doesn't need to include the "dot com" in it - it can be represented just as the two words Exploit Hub.
The logo should convey:
...and again, it should be on a white background.