TSPY_ZBOT.MK
Windows 2000, XP, Server 2003
![](/vinfo/imgFiles/legend.jpg)
Threat Type: Spyware
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This spyware may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.
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. It attempts to steal information, such as user names and passwords, used when logging into certain banking or finance-related websites.
TECHNICAL DETAILS
Arrival Details
This spyware may be dropped by other malware.
It may be unknowingly downloaded by a user while visiting malicious websites.
Installation
This spyware drops copies of itself in the Windows system folder and appends garbage code to the dropped copy to avoid easy detection. The dropped copies uses the following file names:
- sdra64.exe
It injects itself into the following processes running in the affected system's memory:
- SVCHOST.EXE
- WINLOGON.EXE
It creates the following folders with attributes set to System and Hidden to prevent users from discovering and removing its components:
- %System%\lowsec
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
Autostart Technique
This spyware modifies the following registry entry(ies) to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Winlogon
Userinit = %System%\userinit.exe, %System%\sdra64.exe,
(Note: The default value data of the said registry entry is %System%\userinit.exe,.)
It drops the following files:
- %System%\lowsec\local.ds - copy of the encrypted downloaded file
- %System%\lowsec\user.ds - used to save the gathered information
(Note: %System% is the Windows system folder, which is usually C:\Windows\System on Windows 98 and ME, C:\WINNT\System32 on Windows NT and 2000, or C:\Windows\System32 on Windows XP and Server 2003.)
Other System Modifications
This spyware adds the following registry entries as part of its installation routine:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows NT\CurrentVersion\Network
UID = {Computer name}_{Random numbers}
It adds the following registry keys as part of its installation routine:
HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Explorer\{43BF8CD1-C5D5-2230-7BB2-98F22C2B7DC6}
HKEY_USERS\.DEFAULT\Software\
Microsoft\Windows\CurrentVersion\
Explorer\{9E538ED2-437C-088A-86DD-1FE4F7C3145B}
Information Theft
This spyware monitors the Internet Explorer (IE) activities of the affected system, specifically the address bar or title bar. It recreates a legitimate website with a spoofed login page if a user visits banking sites with the following strings in the address bar or title bar:
- http://*myspace.com*
- https://www.gruposantander.es/*
- https://internetbanking.gad.de/*/portal?bankid=*
- https://www.vr-networld-ebanking.de/index.php?RZKZ=*&RZBK=*
- https://finanzportal.fiducia.de/*?rzid=*&rzbk=*
- https://ssl.bsk.com.pl/bskonl/login.ac
- https://*.banking.first-direct.com/*
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.
It accesses the following site to download its configuration file:
- http://{BLOCKED}y.com.cn/catalog/images/default/3.bin
The downloaded file contains information where the malware can download an updated copy of itself, and where to send its stolen data.
It attempts to steal information from the following banks and/or other financial institutions:
- Santader
- Volksbank
- Fiducia
- ING Bank
- First Direct
Stolen Information
This spyware sends the gathered information via HTTP POST to the following URL:
- http://www.{BLOCKED}tek.cn/catalog/images/logos/g.php
SOLUTION
Step 1
For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.
Step 2
Identify and delete files detected as TSPY_ZBOT.MK using either the Startup Disk or Recovery Console
Step 3
Restore this modified registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon
- From: Userinit =%System%\userinit.exe, %System%\sdra64.exe,
To: Userinit =%System%\userinit.exe,
- From: Userinit =%System%\userinit.exe, %System%\sdra64.exe,
Step 4
Delete this registry value
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.
- In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Network
- UID={Computer name}_{Random numbers}
- UID={Computer name}_{Random numbers}
Step 5
Delete this registry key
Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.
- In HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\
- {43BF8CD1-C5D5-2230-7BB2-98F22C2B7DC6}
- {43BF8CD1-C5D5-2230-7BB2-98F22C2B7DC6}
- In HKEY_USERS\.DEFAULT\Software\Microsoft\Windows\CurrentVersion\Explorer\
- {9E538ED2-437C-088A-86DD-1FE4F7C3145B}
- {9E538ED2-437C-088A-86DD-1FE4F7C3145B}
Step 6
Search and delete this folder
- %System%\lowsec\local.ds
Step 7
Scan your computer with your Trend Micro product to delete files detected as TSPY_ZBOT.MK. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.
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