TSPY_ZBOT.MTKR

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

It creates folders where it drops its files.

It modifies the Internet Explorer Zone Settings.

As of this writing, the said sites are inaccessible.

It steals certain information from the system and/or the user.

It deletes the initially executed copy of itself.

Arrival Details

This Trojan Spy 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 Trojan Spy drops the following copies of itself into the affected system and executes them:

• %Application Data%\{random folder 1}\{random filename 1}.exe

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

It drops the following files:

• %Application Data%\{random folder 2}\{random file name 2}.tmp
• %Application Data%\{random folder 2}\{random file name 2}.{random extension}
• %Application Data%\{random folder 3}\{random file name 3}.{random extension}
• %User Temp%\tmp{random characters}.bat -> used to delete the initial copy and itself

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

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

• Local\{GUID}
• Global\{GUID}

It is injected into the following processes running in memory:

• explorer.exe

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random1} = "%Application Data%\{random folder 1}\{random filename 1}.exe"

Other System Modifications

This Trojan Spy adds the following registry entries as part of its installation routine:

HKEY_CURRENT_USER\Software\Microsoft\
{random key}
{random2} = "{Random Bytes}"

Web Browser Home Page and Search Page Modification

This Trojan Spy modifies the Internet Explorer Zone Settings.

Download Routine

This Trojan Spy connects to the following URL(s) to download its configuration file:

• http://{BLOCKED}.{BLOCKED}.54.5/api/home.php

As of this writing, the said sites are inaccessible.

Information Theft

This Trojan Spy steals the following information:

• 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
• Online banking credentials
• Personal digital certificate

Other Details

This Trojan Spy does the following:

• Receive configuration file.
  The received configuration file may contain URLs where it downloads an updated copy of itself and where it sends its gathered information. It may also contain URLs of its target online banking and finance-related sites from where it steals the information. Note that the contents of the file, hence the list of websites to monitor, may change anytime.
• It first injects codes to explorer.exe then to all running processes to perform its routines.

It deletes the initially executed copy of itself