TSPY_ZBOT.BRK

 Analysis by: Kathleen Notario

 PLATFORM:

Windows 2000, XP, Server 2003

 OVERALL RISK RATING:
 REPORTED INFECTION:
 SYSTEM IMPACT RATING:
 INFORMATION EXPOSURE:

  • Threat Type: Spyware

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW


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. It attempts to steal information, such as user names and passwords, used when logging into certain banking or finance-related websites.

It checks for the presence of the following processes which are related to Outpost Personal Firewall and ZoneLabs Firewall Client:

  • outpost.exe
  • zlclient.exe

It terminates if either of the said processes exist. This is to ensure that it runs uninterrupted. It also has rootkit capabilities, which enables it to hide its processes and files from the user.

  TECHNICAL DETAILS

File Size:

233,472 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

17 Sep 2010

Payload:

Downloads files, Drops files, Terminates processes, Hides files and processes, Disables Windows Firewall

Infection Points

This spyware arrives as a file downloaded from the following URLs:

  • http://{BLOCKED}up.com/faq/updates/server/faq.exe

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 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.)

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

  • __SYSTEM__64AD0625__

It injects itself into the following processes as part of its memory residency routine:

  • SVCHOST.EXE
  • WINLOGON.EXE

Autostart Technique

This spyware modifies the following registry entries to ensure it 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,.)

Other System Modifications

This spyware adds the following registry entries:

HKEY_LOCAL_MACHINE
UID = {Computer name}_{Random numbers}

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\SharedAccess\Parameters\
FirewallPolicy\StandardProfile
EnableFirewall = 0

Dropping Routine

This spyware 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.)

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.

It accesses the following site to download its configuration file:

  • http://{BLOCKED}p.com/faq/updates/bins/inf.bin

It attempts to access a website to download a file which contains information where the Trojan can download an updated copy of itself, and where to send its stolen data. This configuration file also contains the following list of targeted bank-related websites from which it steals information:

  • *.citizensbank.com/*passw;loginO
  • http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback&*
  • https://banking.*.de/cgi/ueberweisung.cgi/*
  • https://brokerage.comdirect.de/servlet/*TAN*
  • https://cipehb*.cdg.citibank.de/HomeBanking*?_D=WorkArea&*
  • https://finanzportal.fiducia.de/ebanking*Action=*
  • https://finanzportal.fiducia.de/ebbg2/portal?token=*
  • https://internetbanking.gad.de/banking/*
  • https://online.wellsfargo.com/signon
  • https://onlinebanking.norisbank.de/norisbank/*.do?method=*
  • https://www.bbva.es/BBVANET/app/OperacionCBTFServlet?proceso=BDNTPosGlobalPr&operacion=BDNTPgPosicionGlobalOp&accion=consultar&campo=detallada
  • https://www.bbva.es/TLBS/fbin/bbva_logo_tcm11-13047.gif
  • https://www.bbvanetcash.com/local_tlsb/mult/logo_BBVA_publica_CAS.gif
  • https://www.bbvanetoffice.com/bbvanetoffice/OperacionCBTFServlet?proceso=BDNTPosGlobalPr&operacion=BDNTPgPosicionGlobalOp&accion=consultar&campo=detalla
  • https://www.bbvanetoffice.com/m lt/logo_nuevo.gif
  • https://www.citibank.de/*/jba/mp#/SubmitRecap.do
  • https://www.dresdner-privat.de/servlet/*
  • https://www.moneybookers.com/images/qimage.gif
  • https://www.vr-networld-ebanking.de/ebanking*Action=*

Note that the contents of the file, hence the list of websites to monitor, may change any time.

It attempts to steal information from the following banks and/or other financial institutions:

  • BBVA
  • Citibank
  • Citizens Bank
  • Comdirect
  • Dresdner
  • Ebay
  • Fiducia
  • GAD
  • IS Bank
  • Moneybookers
  • Volksbanken Raiffeisenbanken
  • Wells Fargo

Stolen Information

The stolen information is saved in the following file:

  • %System%\lowsec\user.ds

(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.)

It sends the gathered information via HTTP POST to the following URL:

  • http://{BLOCKED}up.com/faq/post.php

Other Details

This spyware checks for the presence of the following processes which are related to Outpost Personal Firewall and ZoneLabs Firewall Client:

  • outpost.exe
  • zlclient.exe

It terminates if either of the said processes exist. This is to ensure that it runs uninterrupted. It also has rootkit capabilities, which enables it to hide its processes and files from the user.

Variant Information

This spyware has the following MD5 hashes:

  • 356e68744e3499d17079d0962cdc796a

It has the following SHA1 hashes:

  • 9b94eaac2cfed38fe78030da6feb1a5599457bad

  SOLUTION

Minimum Scan Engine:

8.900

VSAPI PATTERN File:

currently processing

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.BRK using the Recovery Console

[ Learn More ]

Step 3

Restore this modified registry value

[ Learn More ]

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: %System%\userinit.exe,

Step 4

Delete this registry value

[ Learn More ]

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}
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\SharedAccess\Parameters\FirewallPolicy\StandardProfile
    • EnableFirewall=0

Step 5

Search and delete this folder

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.  %System%\lowsec

Step 6

Scan your computer with your Trend Micro product to delete files detected as TSPY_ZBOT.BRK. 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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