Hi, Saw this one on www.waraxe.us (Discovered by Easyex) and i was thinking if there are some more possibilities using the method described. The POC below is for phpBB. - ========== make yourself a folder on your host rename the folder to signature.jpg this will trick bbcode that its an image file. example http://sitewithmaliciouscode/signature.jpg inside that folder .. put this code .. and rename it to index.php file. Quote: this will make every visitor getting logout when they view the thread that have image linked to this. =================== This seems to be working on almost all the scripts using BBcode. Successfully tested on vBulletin 3.0.7 and phpBB 2.0.17 when used the image link to the folder with the malicious code as the forum signature. What i was wondering is there anything more serious than logging out the users that can be done with this? The admin folders of ipb and phpbb need reauthentication. So nothing serious for them but anything more innovative that could be done? And any way to fix this? Regards, -- http://www.h4cky0u.org (In)Security at its best... _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/