TROJ_BANKER.LWY
Windows 2000, XP, Server 2003
Threat Type: Trojan
Destructiveness: No
Encrypted: No
In the wild: Yes
OVERVIEW
This Trojan 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. 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 Trojan 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 drops the following copies of itself into the affected system:
- %Application Data%\explore.exe
(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 drops the following non-malicious files:
- %System%\drivers\banking.sys
(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 Trojan adds the following registry entries to enable its automatic execution at every system startup:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
@ = %Application Data%\explore.exe
Other System Modifications
This Trojan adds the following registry keys:
HKEY_CURRENT_USER\explore
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\banking
Information Theft
This Trojan 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:
- Banco Itau - Feito Para Voce
- Banco Santander (Brasil) S.A.
- Banco do Brasil
- Banrisul
- Bradesco
- Brasil
- CEF
- Caixa
- Portal Internet Banrisul
- Santander
- Serasa
- Serasa Experian
- bb.com.br
- http://www.bb.com.br
- http://www.bradesco.com.br
- http://www.bradescocorporate.com.br
- http://www.bradescoempresas.com.br
- http://www.bradescopessoajuridica.com.br
- http://www.bradescoprime.com.br
- http://www.itau.com.br
- http://www.itaupersonnalite.com.br
- http://www.itaupersonnalite.com.br
- http://www.itauprivatebank.com.br
- http://www.santander.com.br
- https://internetbanking.caixa.gov.br
- https://www.caixa.gov.br
- https://www2.bancobrasil.com.br
- https://wwwss.bradesco.com.br
The spoofed login overlaps the legitimate login area of the website, thus tricking the user into thinking that it is part of the IE window. The spoofed login page is located in a fixed area of the legitimate website. The said routine tricks the user into giving out sensitive account-related information. It then logs keystrokes entered by the user in the user name and password fields of the spoofed login page.
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 from the following banks and/or other financial institutions:
- Banco Caixa
- Banco Itau
- Banco Santander
- Banco Serasa
- Banco do Brasil
- Banrisul
- Bradesco
- Brasil
- Caixa Economica Federal
- Santander
Stolen Information
This Trojan sends the gathered information via HTTP POST to the following URL:
- http://www.{BLOCKED}b.net/enviador.php
- http://{BLOCKED}eam.com/envia.php
Other Details
This Trojan did not exhibit propagation routines during testing.
It did not exhibit download routines during testing.
It did not exhibit backdoor routines during testing.
Variant Information
This Trojan has the following MD5 hashes:
- b0de5a2bdc3d66ce80f602872735c8dc
It has the following SHA1 hashes:
- 4862b623c620e3c79ffe085fed0051bb9883bab7
SOLUTION
Step 1
Identify and terminate files detected as TROJ_BANKER.LWY
- If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
- If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.
Step 2
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\CurrentVersion\Run
- @ = %Application Data%\explore.exe
- @ = %Application Data%\explore.exe
Step 3
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.
- In HKEY_CURRENT_USER\
- explore
- explore
- In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\
- banking
- banking
Step 4
Search and delete this file
- %System%\drivers\banking.sys
Step 5
Scan your computer with your Trend Micro product to delete files detected as TROJ_BANKER.LWY. 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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