Welcome to HBH! If you had an account on hellboundhacker.org you will need to reset your password using the Lost Password system before you will be able to login.
Test
Test of regex: http://www.hellboundhackers.org/news.php?logout=true w00t! Test of new regex: [img]http://www.hellboundhackers.org/news.php?logout=true[/img] Test of newer regex:[img]http://hellboundsecurity.org/fusion_admin/index.php[/img]
Basically, the logout page has a CSRF vulnerability.
This means that whenever anyone loads the page the get logged out, simple
They get logged out because browsers interpret images as html pages and request them using the standard HTTP GET
This means that cookies and headers can be pass with them
The problem is not people posting images but the vulnerability in the logout page - I think that the admins haven't had time to address this or didn't know how it worked