TSPY_ZBOT.SMYX

This spyware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Arrival Details

This spyware arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

This spyware drops the following files:

• %Application Data%\{random1}\{random}.exe
• %Application Data%\{random2}\{random}.{random}

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It creates the following folders:

• %Application Data%\{random1}
• %Application Data%\{random2}

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• Global\{GUID}
• Local\{GUID}

It is injected into the following processes running in memory:

• ctfmon.exe
• dwm.exe
• explorer.exe
• rdpclip.exe
• taskeng.exe
• taskhost.exe
• wscntfy.exe

Autostart Technique

This spyware adds the following registry entries to enable its automatic execution at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
GUID = %Application Data%\{random1}\{random}.exe

Other System Modifications

This spyware adds the following registry keys as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
{random}

Download Routine

This spyware accesses the following websites to download files:

• http://{pseudorandom alpha characters}.{BLOCKED}z/forum/
• http://{pseudorandom alpha characters}.{BLOCKED}g/forum/
• http://{pseudorandom alpha characters}.{BLOCKED}o/forum/
• http://{pseudorandom alpha characters}.{BLOCKED}t/forum/
• http://{pseudorandom alpha characters}.{BLOCKED}m/forum/

NOTES:
It may connect to a remote URL to download its configuration file. The said file contains information where the malware can download an updated copy of itself, and where to send its stolen data. It also contains a list of targeted bank-related websites from which it steals information. The URL where it connects to is randomly generated using a randomizing function, which is computed based on the system's current date. However, as of this writing, none of the sites were accessible. It may also gather the following information from the affected system:

• Data on Cookie files (URLs)
• Email information stored in the user’s Windows Address Book (WAB) file