Backdoor.Win32.Clampi.a

Technical Details

This Trojan spy program is designed to steal confidential user data and remotely manage the victim machine. It is a Windows PE EXE file. It is 470 bytes in size.

Installation

When launched, the Trojan creates the following file:

%AppData%\<name>.exe

<name&gr; is chosen at random from the list below:

dumpreport
msiexeca
svchosts
upnpsvc
service
taskmon
rundll
helper
event
logon
sound
lsas

In order to ensure that the Trojan is launched automatically when the system is rebooted, the Trojan adds a link to its executable file in the system registry:

HKLM\Software\Microsoft\Windows\CurrentVersion\Run]
"<name2>" = %AppData%\<name>.exe|

<name2> is chosen at random from the list below:

CrashDump 
svchosts 
EventLog 
TaskMon 
Windows 
RunDll 
System 
Setup 
Sound 
lsass 
UPNP 
Init

Payload

The Trojan connects to servers to download and run malicious code. The server addresses are saved to the system registry key shown below:

The Trojan saves its settings to the registry keys shown below:

The malicious code downloaded from the servers is designed to harvest information from the victim machine (user name, login data, program passwords, local and network passwords).

The Trojan can also be configured to steal login and password data for Internet banking systems by substituting spoofed pages for genuine banking system pages. The program targets popular financial organizations such as the ones listed below:

https://www.hsbc.co.uk
https://www.mybusinessbank.co.uk
https://investing.schwab.com

The Trojan will regularly download updates to its code and additional modules. The programs downloaded include:

• Trojan programs designed to steal bank account data
• Trojans designed to steal passwords to common applications such as:

Browsers

• IE Password Protected Sites
• IE AutoComplete Fields
• Firefox
• Opera

Messengers

• MSN Messenger
• ICQ
• IRQ
• Trillian
• Miranda IM
• Camfrog Video Chat
• Easy Web Cam
• Google Talk

FTP Programs

• Total Commander
• WS FTP
• SecureFX FTP
• WebDrive Ftp
• FtpVoyager
• AutoFTP
• FTP Control
• 32bit Ftp
• FTP Navigator
• Far FTP
• FlashFXP FTP
• CuteFTP
• CoffeeCup FTP
• FileZilla FTP
• FTP Now
• CoreFTP
• SmartFTP

Other Programs

• Outlook Express
• Dial Up
• VNC
• Remote Desktop
• WinProxy
• Google Desktop

Network propagation

In order to spread via the local network, the Trojan ties to copy itself to network machines by using ipc$ and admin$ and also shared folders. In order to launch itself on networked machines, the Trojan uses a legitimate utility, Sysinternal's psexec.exe.

Note

In order to prevent the malicious program spreading via networks, servers used by domain administrators should be disinfected. Additionally strong passwords should be used on local machines.

The Trojan downloads a variety of code from servers. This code can be modified or replaced with other malicious code. At the time of writing, the Trojan was configured to connect to the addresses listed below:

panel.***boora.cn
147.202.39.***
174.36.82.***        
195.12.38.***
195.189.247.***
195.225.236.***
205.234.231.***
209.51.159.***
209.85.120.***
61.153.3.***
64.18.143.***
66.128.55.***
66.199.237.***
66.199.237.***
66.225.237.***
66.7.197.***
75.102.23.***

The Trojan only runs on English versions of Windows.

Removal instructions

If your computer does not have an up-to-date antivirus, or does not have an antivirus solution at all, follow the instructions below to delete the malicious program:

1. Use Task Manager to terminate the malicious process.
2. Delete the original backdoor file (the location will depend on how the program originally penetrated the victim machine).
3. Delete the file created by the backdoor:

   %AppData%\<name>.exe

4. Delete the following system registry key:

   HKLM\Software\Microsoft\Windows\CurrentVersion\Run]
   "<name2>" = %AppData%\<name>.exe

Update your antivirus databases and perform a full scan of the computer (download a trial version of Kaspersky Anti-Virus).