Asseco SEE iBank FX Client <= 2.0.9.3 Local Privilege Escalation Vulnerability

Title: Asseco SEE iBank FX Client <= 2.0.9.3 Local Privilege Escalation Vulnerability
Advisory ID: ZSL-2014-5168
Type: Local
Impact: Privilege Escalation
Risk: (2/5)
Release Date: 06.02.2014
Summary
FX Client is an offline application for e-banking that is intended only for legal entities.
Description
The application is vulnerable to an elevation of privileges vulnerability which can be used by a simple user that can change the executable file with a binary of choice. The vulnerability exist due to the improper permissions, with the 'F' flag (full) for the 'Everyone' and 'Users' group, for the 'RichClient.exe' and 'fxclient.exe' binary files making them world-writable. After you replace the binary with your rootkit, on reboot you get SYSTEM privileges.
Vendor
Asseco SEE - http://www.asseco.com
Affected Version
2.0.9.3 (Build 22.06.2011) - Desktop/Enterprise Edition
1.2
1.1.5.1270 (Service Pack 5) - Desktop Edition
1.1.5.1247
1.0
Tested On
Microsoft Windows 7 Ultimate SP1 (EN) 32/64bit
Microsoft Windows 7 Professional SP1 (EN) 32/64bit
Microsoft Windows XP Professional SP3 (EN) 32bit
Vendor Status
N/A
PoC
fxclient_pe.txt
Credits
Vulnerability discovered by Gjoko Krstic - <gjoko@zeroscience.mk>
References
[1] http://www.exploit-db.com/exploits/31460/
[2] http://cxsecurity.com/issue/WLB-2014020053
[3] http://packetstormsecurity.com/files/125093
[4] http://1337day.com/exploit/21865
[5] http://osvdb.org/show/osvdb/103048
[6] http://www.securityfocus.com/bid/65456
Changelog
[06.02.2014] - Initial release
[07.02.2014] - Added reference [2], [3] and [4]
[09.02.2014] - Added reference [5]
[12.02.2014] - Added reference [6]
Contact
Zero Science Lab

Web: http://www.zeroscience.mk
e-mail: lab@zeroscience.mk