__Summary The javascript security manager usually prevents that a javascript: URL from one host is opened in a window displaying content from another host. But when the link is dropped to a tab, the security manager does not kick in. This can lead to several security problems scaling from stealing session cookies to the ability to run arbitrary code on the client system (depending on the displayed site or security setttings). Tabbed browsing is a great feature to organize mutliple website, but after a while also tabs become too much. Now you have two options: Close tabs and open new ones (CTRL+W to close a tab, followed by a CTRL+click on a link to open a new one), or just recycle already open tabs by dragging links to them - the solution i prefer. __Proof-of-Concept http://www.mikx.de/firetabbing/ __Status The bug is marked as fixed in bugzilla. Get a nightly build, compile on your own or wait for Firefox 1.0.1. 2005-01-27 Vendor informed (bugzilla.mozilla.org #280056) 2005-01-28 Vendor confirmed bug 2005-02-05 Vendor fixed bug 2005-02-07 Public disclosure The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0231 to this issue. __Affected Software Tested with Firefox 1.0 and Mozilla 1.7.5 __Contact Informations Michael Krax http://www.mikx.de/?p=9 mikx