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COMMAND IE SYSTEMS AFFECTED IE PROBLEM Perkere Stinker found following. It's trivial to trick a user into accepting a bookmark for a popular site, uh, lets say www.hotmail.com .. or placing it yourself. Users wont be able to access www.hotmail.com by typing the url in the address bar, they'll get redirected to whatever the bookmark points to. This could easily be used for putting up 'fake pages' on public accessible computers, like at libraries, schools etc. Where pages like hotmail/google/msn are often accessed. That could give you a lot of nice usernames/passwords. And a lot of crap. It's fairly feasible concept. 1) attacker places javascript on a public website to add a bookmark for www.onlinebankx.com (and possibly other commonly visited sites where a username and a password might be needed) which is actually www.attackersite.com. 2) attacker sets up a mirror of www.onlinebankx.com on www.atackersite.com. 3) attacker then sets up some method to draw people to visit public website (free porn, for example). 4) victim visits public website, gets several bookmarks added. 5) if the attacker is lucky, the victim eventually goes to visit one of those bookmarks which pulls up the fake site. 6) victim enters their username and password for www.onlinebankx.com at which time the attacker records such information as entered. 7) an error page is then displayed and victim is then forwarded on to the real site, unaware that their username and password have been obtained by the attacker. Combine step 1 with placing malicious javascript on vulnerable ida iis sites, and a worm to deliver such a package, and the number of possibilities for this scenerio to work gets higher. The only two dependent variables are: wether joe user running IE visits a bookmark effecting site and wether joe user will go to a possibly redirected website. Examples: 1) searched and replaced bookmark for yahoo.com or google.com. They are replaced with commands such as rdisk or perhaps something else with user-level priv instead. The next time the user wishes to search, they are confused and hacked (cracked.. whatever). this is not a social engineered exploit, it's a logical one. 2) links in email or web content which say one thing such as "you have a new greeting card at www.sweethearts.com", which point to a malicious site instead (Favorites change has occurred), which the attacker has crafted to error out (yet running malicious script quietly in the background) then redirects to the real site. This is YOUR combo of social/logical. 3) and just to bring up my favorite subject again, add Raw Socket priv's for all users to this equation...you do the math. The possibilities then become endless! Another thing was pointed out by Kyle L. He was playing with Favorites and added a favorite with the name of 'www.dsakfjhasdfj.com' and set it to point to the address 'c:\command.com'. dont include the '' characters..... He then typed in 'www.dsakfjhasdfj.com' in the address bar and it loaded up the msdos command prompt window. You can write a javascript to add a Favorite or edit Startpage in internet explorer. A window usually pops up asking if you want to add it as a Favorite or Startpage, but if the security settings are low, it would automatically do it without asking. You could make the favorite point to files on the local system and have them executed. SOLUTION Opera and netscape both do not direct themselvs to a bookmark-title location. Also, netscape and opera do not support the remotee-bookmark placing 'feature'. Anyway, why to use browser anyway ;)