VMrc vulnerable to format string attacks. Exploitation of this issue may lead to arbitrary code execution on the system where VMrc is installed.

Digital Security Research Group [DSecRG] Advisory DSECRG-09-053:
http://www.dsecrg.com/pages/vul/show.php?id=153

Application: VMware Remoute Console
Version: e.x.p build-158248
Vendor URL: http://vmware.com
Bugs: Format String Vulnerabilitys
Exploits: YES (PoC)
Reported: 07.08.2009
Vendor response: 13.08.2009
Date of Public Advisory: 09.04.2010
CVE: CVE-2009-3732
VSA: VMSA-2010-0007
Authors: Alexey Sintsov of
Digital Security Research Group [DSecRG] (research [at] dsecrg [dot] com)



Description
********

VMware Remote Console Plug-in can be installed from WEB
interface of VMware vSphere. This software contains of ActiveX
objects and executable files for remote console of guest OS.
VMrc vulnerable to format string attacks. Exploitation of this issue
may lead to arbitrary code execution on the system where VMrc is installed.


Details
*******

Attacker can make shortcut with special parameters for
vmware-vmrc.exe and bad MOID or HOST parameter. If a user try to use
this shortcut to connect to vSphere server he will see next message
box:

"Error opening the remote virtual
machine HOST\MOID: The object has already been deleted
or has not been completely created."

If user name or password will be incorrect the user also gets error
message box.

Parameters HOST and MOID are addicted to format injection.

Also this vuln. can be exploited remotely by special crafted html page.

ActiveX element: clsid:B94C2238-346E-4C5E-9B36-8CC627F35574

Attacker can rewrite stack data and may be it's possible to code
execution.



Example(shortcut):
*****************

C:\Program Files\Common Files\VMware\VMware Remote Console Plug-in>vmware-vmrc.exe -u vmware_user -h HOST -M AAAA:%x.%x.%x.%x.:BBBB

VMDlg::ShowDialog: Error opening the remote virtual machine
HOST\AAAA:3455600.78138a94.100012b2.28e27b0.:BBBB:

Example(ActiveX):
****************

objectVMRC.connect ("host" ,"username" ,"password",
"%x:%x:%x:%x:%x:%x:%x:%x:%x" ,"X" ,2);


Fix Information
***************
VMware has released the following patch for
ESX 4.0: ESX400-200911223-UG

Also this issue solved in vCenter 4.0 Update 1

References
**********

http://dsecrg.com/pages/vul/show.php?id=153
http://lists.vmware.com/pipermail/security-announce/2010/000090.html

About
*****

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Digital Security Research Group focuses on web application and database
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Contact: research [at] dsecrg [dot] com
http://www.dsecrg.com