Modified by: Kathleen Notario

ALIASES:

Trojan.Zbot!gen14 (Symantec); Trojan-Spy.Win32.Zbot.avfi (Kaspersky)

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

  TECHNICAL DETAILS

File Size: 155,648 bytes
File Type: PE
Memory Resident: Yes
Initial Samples Received Date: 04 Dec 2010
Payload: Drops files

Arrival Details

This spyware may be unknowingly downloaded by a user while visiting the following malicious websites:

  • http://{BLOCKED}sein.net/22oct_pac.exe

Installation

This spyware adds the following folders:

  • %Application Data%\{random1}
  • %Application Data%\{random2}

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

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

  • dwm.exe
  • rdpclip.exe
  • ctfmon.exe
  • wscntfy.exe
  • taskeng.exe
  • taskhost.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
{random CLSID} = %Application Data%\{random1}\{random}.exe

Other System Modifications

This spyware adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
{random}

Dropping Routine

This spyware drops the following files:

  • %Application Data%\{random1}\{random}.exe
  • %Application Data%\{random2}\{random}.{random}

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming on Windows Vista and 7.)

Download Routine

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

  • http://{BLOCKED}adus.cc/spm.cpm

Information Theft

This spyware 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:

  • *.abbeynational.co.uk/*
  • *.barclays.co.uk*
  • *.barclays.co.uk*barcaz.php*
  • *.barclays.co.uk*bg.php*
  • *.firstdirect.com*splash*trusteer*
  • *.firstdirect.com/1/2/*
  • *.hsbc.co.uk/1*
  • *.mybank.alliance-leicester.co.uk*
  • *abbeynational.co.uk*abbeyaz.*php*
  • *abbeynational.co.uk*bg.php*
  • *alliance*leicester.co.uk*bg.php*
  • *alliance*leicester.co.uk*leicesteraz.php*
  • *firstdirect.com*bg.php*
  • *firstdirect.com*firstaz.php*
  • *hsbc.co.uk*az.php*
  • *hsbc.co.uk*bg.php*
  • *lloydstsb.co*
  • *lloydstsb.co*az.php*
  • *lloydstsb.co*bg.php*
  • *nwolb.co*
  • *nwolb.co*az.php*
  • *nwolb.co*bg.php*
  • *retail.abbeynational.co.uk/EBAN_ENS/BtoChannelDriver.ssobto*
  • http://lloydstsb.personal-banking.cc/js/lloydstsbaz.js
  • http://lloydstsb.personal-banking.cc/lloydstsb/bg.php
  • http://myonlineaccounts2.abbeynational.servat.cc/abbey/bg.php
  • http://myonlineaccounts2.abbeynational.servat.cc/js/abbeyaz.js
  • http://www.barclayscouk.cc/barc/bg.php
  • http://www.barclayscouk.cc/js/barcaz.js
  • http://www.mybank.alliance-leiceter.cc/js/leicesteraz.js
  • http://www.mybank.alliance-leiceter.cc/leicester/bg.php
  • http://www.nsvc.cc/az.js
  • http://www.nsvc.cc/hsbc/bg.php
  • http://www.nwolb.co.uk.servat.cc/js/natwestaz.js
  • http://www.nwolb.co.uk.servat.cc/natwest/bg.php
  • http://www1.banking.firstdirest.cc/first/bg.php
  • http://www1.banking.firstdirest.cc/js/firstaz.js

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

  • Alliance & Leicester
  • Barclays
  • First Direct
  • HSBC
  • Lloyds
  • Natwest
  • Santander

Stolen Information

This spyware sends the gathered information via HTTP POST to the following URL:

  • http://{BLOCKED}cyis.com/yahooman.php

Variant Information

This spyware has the following MD5 hashes:

  • f600dd8d561c4b9b8c03e02ae0535e69

It has the following SHA1 hashes:

  • 1d474f3f1c26c81f3465d942edc7abd0b9f6902c

  SOLUTION

Minimum Scan Engine: 8.900
VSAPI PATTERN File: 7.674.11
VSAPI PATTERN Date: 04 Dec 2010
VSAPI PATTERN Date: 12/4/2010 12:00:00 AM

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Identify and delete files detected as TROJ_ZBOT.BYR using the Recovery Console

[ Learn More ]

Step 3

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • {random CLSID}=%Application Data%\{random1}\{random}.exe

Step 4

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_ZBOT.BYR. 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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