Analysis by: jasperm
ALIASES:

Backdoor:Win32/Qakbot (Microsoft); Net-Worm.Win32.Kolab.ucv (Kaspersky)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel: Propagates via network shares

This worm may be dropped by other malware. It may be unknowingly downloaded by a user while visiting malicious websites.

It also has rootkit capabilities, which enables it to hide its processes and files from the user.

  TECHNICAL DETAILS

File Size: 201,728 bytes
File Type: PE
Memory Resident: Yes
Initial Samples Received Date: 23 Feb 2011
Payload: Downloads files, Drops files, Steals information, Hides files and processes, Blocks access to certain websites

Arrival Details

This worm may be dropped by other malware.

It may be unknowingly downloaded by a user while visiting malicious websites.

Installation

This worm drops the following files:

  • %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}\{random name}.exe - copy of itself
  • %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}\{random name}.dll - dll component also WORM_QAKBOT.USL
  • %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}\{random name}.dll - encrypted configuration file

It creates the following folders:

  • %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}
  • %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}\u\

It is injected into the following processes running in memory:

  • EXPLORER.EXE
  • IEXPLORE.EXE

Autostart Technique

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

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{random name} = "%System Root%\Documents and Settings\All Users\Application Data\Microsoft\{random folder name}\{random file name}.exe"

It modifies the following registry entries to ensure it automatic execution at every system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
{legitimate application} = ""%System Root%\Documents and Settings\All Users\Application Data\Microsoft\{random folder name}\{random file name}.exe" /c {path and file name of legitimate application}"

(Note: The default value data of the said registry entry is {path and file name of legitimate application}.)

Rootkit Capabilities

This worm also has rootkit capabilities, which enables it to hide its processes and files from the user.

NOTES:

Propagation

This worm enumerates network shares and drops a copy of the main executable and the package file to default shares.

Payload

This worm's configuration file contains the following information:

  • Reference to the components and their corresponding random file names in the system
  • IRC data
  • FTP hosts (upload sites)
  • infection log

It is capable of monitoring the browsing activities of the infected computer and logs all information related to finance-related websites containing the following strings:

  • /cashman/
  • /cashplus/
  • /cmserver/
  • access.jpmorgan.com
  • businessaccess.citibank.citigroup.com
  • business-eb.ibanking-services.com
  • businessonline.huntington.com
  • cashproonline.bankofamerica.com
  • cpw-achweb.bankofamerica.com
  • directline4biz.com
  • directpay.wellsfargo.com
  • ebanking-services.com
  • express.53.com
  • ibc.klikbca.com
  • itreasury.regions.com
  • itreasurypr.regions.com
  • ktt.key.com
  • moneymanagergps.com
  • netconnect.bokf.com
  • onb.webcashmgmt.com
  • onlineserv/CM
  • premierview.membersunited.org
  • singlepoint.usbank.com
  • tmconnectweb
  • treas-mgt.frostbank.com
  • treasury.pncbank.com
  • web-cashplus.com

It may also collect the following information:

  • Account name
  • City
  • Country
  • IE password protected sites
  • IE user names and passwords
  • IP address
  • MSN user name and password
  • Operating system
  • Outlook user name and password

This worm blocks access to websites with the following strings:

  • .eset
  • agnitum
  • ahnlab
  • arcabit
  • avast
  • avg
  • avira
  • avp
  • bit9
  • bitdefender
  • castlecops
  • centralcommand
  • clamav
  • comodo
  • computerassociates
  • cpsecure
  • defender
  • drweb
  • emsisoft
  • esafe
  • etrust
  • ewido
  • fortinet
  • f-prot
  • f-secure
  • gdata
  • grisoft
  • hacksoft
  • hauri
  • ikarus
  • jotti
  • k7computing
  • kaspersky
  • malware
  • mcafee
  • networkassociates
  • nod32
  • norman
  • norton
  • panda
  • pctools
  • prevx
  • quickheal
  • rising
  • rootkit
  • securecomputing
  • sophos
  • spamhaus
  • spyware
  • sunbelt
  • symantec
  • threatexpert
  • trendmicro
  • virus
  • webroot.
  • wilderssecurity
  • windowsupdate
It does not continue its routine if its host process is any of the following:
  • ctfmon.exe
  • dbgview.exe
  • mirc.exe
  • msdev.exe
  • ollydbg.exe

This worm also drops a JavaScript (JS) file detected as JS_QAKBOT.SM which is responsible for downloading updated components of this malware. It then creates a scheduled task that executes this script every four hours.

It downloads updated components from the following websites:

  • {BLOCKED}rv.co.in
  • {BLOCKED}01.in
  • {BLOCKED}ver.com.ua
  • {BLOCKED}03.com.ua

It saves the downloaded components in the following folder:

  • %System Root%\Documents and Settings\All Users\Application Data\Microsoft\{random folder}\u

It sends the information gathered to the following sites using credentials from its configuration file:

  • {BLOCKED}.{BLOCKED}.134.75
  • ftp.{BLOCKED}formation.com
  • ftp.{BLOCKED}scentral.com
  • s046.{BLOCKED}oxmanager.com

It may also connect to IRC servers and receive commands from a remote user.

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.852.15
FIRST VSAPI PATTERN DATE: 23 Feb 2010

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

Remove malware files dropped/downloaded by WORM_QAKBOT.USL

    • JS_QAKBOT.SM

Step 3

Identify and delete files detected as WORM_QAKBOT.USL using either the Startup Disk or Recovery Console

[ Learn More ]

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\CurrentVersion\Run
    • {random name} = %System Root%\Documents and Settings\All Users\Application Data\Microsoft\{random folder name}\{random file name}.exe

Step 5

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\CurrentVersion\Run
    • From: {legitimate application} = %System Report%\Documents and Settings\All Users\Application Data\Microsoft\{random folder name}\{random file name}.exe /c {path and file name of legitimate application}
      To: {legitimate application} = {path and file name of legitimate application}

Step 6

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 Root%\Documents and Settings\All Users\Application Data\Microsoft\{random folder name}

Step 7

Scan your computer with your Trend Micro product to delete files detected as WORM_QAKBOT.USL. 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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