Outpost Bypassing Self-Protection using file links Vulnerability

[Matousec - Transparent security Research <research () matousec com>]

Hello,

We would like to inform you about a vulnerability in Outpost Firewall PRO 4.0.


Description:

Outpost protects its files and forbids other applications to manipulate them. Files and directories in its installation 
directory are guarded by various SSDT hooks. However, the implementation of this protection does not prevent malicious 
applications to call native API ZwSetInformationFile class FileLinkInformation. Such calls can be used to replace files 
that are not used by the system when this function is called. One of vulnerable files in the Outpost installation 
directory is SandBox.sys, the driver that implements Outpost Self-Protection mechanisms. Attackers are able to replace 
this driver with a fake copy that will be loaded into the system after the next reboot. This can result in a complete 
system control because driver's code is executed in the privileged kernel mode. The fake driver can be implemented such 
that the user has no chance to notice the attack.



Vulnerable software:

    * Outpost Firewall PRO 4.0 (1005.590.123)
    * Outpost Firewall PRO 4.0 (971.584.079)
    * Outpost Firewall PRO 4.0 (964.582.059)
    * probably all older versions of Outpost Firewall PRO 4.0
    * possibly older versions of Outpost Firewall PRO



More details and a proof of concept including its source code are available here:
http://www.matousec.com/info/advisories/Outpost-Bypassing-Self-Protection-using-file-links.php


Regards,

--
Matousec - Transparent security Research
http://www.matousec.com/