TSPY_ZBOT.ET

This spyware arrives as an attachment to email messages spammed by other malware/grayware or malicious users. It arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It attempts to steal sensitive online banking information, such as user names and passwords. This routine risks the exposure of the user's account information, which may then lead to the unauthorized use of the stolen data.

Arrival Details

This spyware arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

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

It may be downloaded from the following remote sites:

• http://{BLOCKED}n58830039849367.permitds.com/confirm/req/updateflash.exe

Installation

This spyware drops the following files:

• %Application Data%\{random1}\{random}.exe - copy of itself
• %Application Data%\{random2}\{random}.{random} - encrypted file

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

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:\Windows\Profiles\{user name}\Application Data on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Application Data on Windows NT, and C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, XP, and Server 2003.)

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 entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile\AuthorizedApplications\
List
%Windows%\explorer.exe = %Windows%\explorer.exe:*:Disabled:Windows Explorer

It 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}.biz/forum/
• http://{pseudorandom alpha characters}.org/forum/
• http://{pseudorandom alpha characters}.info/forum/
• http://{pseudorandom alpha characters}.net/forum/
• http://{pseudorandom alpha characters}.com/forum/

Information Theft

This spyware attempts to steal sensitive online banking information, such as user names and passwords. This routine risks the exposure of the user's account information, which may then lead to the unauthorized use of the stolen data.

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-related information such as account names, email addresses, passwords, server data, and server port
• Email information stored in the user’s Windows Address Book (WAB) file