WORM_DORKBOT.YBC

 Analysis by: Christopher Daniel So
 Modified by: Rika Joi Gregorio

 PLATFORM:

Windows

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

  • Threat Type: Worm

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Propagates via removable drives

This worm arrives via removable drives.

It executes commands from a remote malicious user, effectively compromising the affected system.

  TECHNICAL DETAILS

File Size:

188,416 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

14 Oct 2014

Payload:

Drops files, Steals information

Arrival Details

This worm arrives via removable drives.

Installation

This worm drops the following copies of itself into the affected system:

  • %Application Data%\ScreenSaverPro.scr
  • %Application Data%\temp.bin
  • %Application Data%\Microsoft\Tnrwrp.exe

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Screen Saver Pro 3.1 = "%Application Data%\ScreenSaverPro.scr"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
Tnrwrp = "%Application Data%\Microsoft\Tnrwrp.exe"

Other System Modifications

This worm adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Applets\
Paint

Propagation

This worm drops the following copy(ies) of itself in all removable drives:

  • {random file name}

It propagates via the following social networking sites:

  • Bebo - in comments and messages
  • Friendster - in messages, comments, shoutouts, chat
  • Twitter - in tweets and direct messages
  • Facebook - in messages, chat, and status updates

Backdoor Routine

This worm executes the following commands from a remote malicious user:

  • Block DNS
  • Create processes
  • Download other files
  • Insert iFrame tags into HTML files
  • Join an IRC channel
  • Log in to FTP sites
  • Perform Slowloris, UDP, and SYN flooding
  • Run Reverse Socks4 proxy server
  • Send MSN Messenger messages
  • Steal login credentials
  • Update itself
  • Visit a web site

It connects to the following URL(s) to send and receive commands from a remote malicious user:

  • h.{BLOCKED}11128.com
  • h.{BLOCKED}aa28.com
  • h.{BLOCKED}28228.com

Other Details

This worm connects to the following URL(s) to get the affected system's IP address:

  • http://api.wipmania.com/
  • http://api.wipmania.net/icon/n.api

NOTES:

This worm drops .LNK files in removable drives. These dropped .LNK files use the names of the folders and files located on the said drives for their file names.

It monitors the user's browsing activities. It gathers the user's login ID, password, and email when the site accessed by the user contains the following strings:

  • *.moneybookers.*/*login.pl
  • *1and1.com/xml/config*
  • *4shared.com/login*
  • *:2082/login*
  • *:2083/login*
  • *:2086/login*
  • *:2222/CMD_LOGIN*
  • *alertpay.com/login*
  • *aol.*/*login.psp*
  • *bcointernacional*login*
  • *bebo.*/c/home/ajax_post_lifestream_comment
  • *bebo.*/c/profile/comment_post.json
  • *bebo.*/mail/MailCompose.jsp*
  • *bigstring.*/*index.php*
  • *clave=*
  • *depositfiles.*/*/login*
  • *dotster.com/*login*
  • *dyndns*/account*
  • *enom.com/login*
  • *facebook.*/ajax/*MessageComposerEndpoint.php*
  • *facebook.*/ajax/chat/send.php*
  • *facebook.*/login.php*
  • *fastmail.*/mail/*
  • *fileserv.com/login*
  • *filesonic.com/*login*
  • *FLN-Password=*
  • *freakshare.com/login*
  • *friendster.*/rpc.php
  • *friendster.*/sendmessage.php*
  • *gmx.*/*FormLogin*
  • *godaddy.com/login*
  • *google.*/*ServiceLoginAuth*
  • *hackforums.*/member.php
  • *hotfile.com/login*
  • *letitbit.net*
  • *login.live.*/*post.srf*
  • *login.yahoo.*/*login*
  • *login_password=*
  • *LoginPassword=*
  • *loginUserPassword=*
  • *mediafire.com/*login*
  • *megaupload.*/*login*
  • *members*.iknowthatgirl*/members*
  • *members.brazzers.com*
  • *moniker.com/*Login*
  • *namecheap.com/*login*
  • *netflix.com/*ogin*
  • *netload.in/index*
  • *officebanking.cl/*login.asp*
  • *oron.com/login*
  • *Passwd=*
  • *Password=*
  • *paypal.*/webscr?cmd=_login-submit*
  • *runescape*/*weblogin*
  • *screenname.aol.*/login.psp*
  • *secure.logmein.*/*logincheck*
  • *sendspace.com/login*
  • *service=youtube*
  • *signin.ebay*SignIn
  • *sms4file.com/*/signin-do*
  • *speedyshare.com/login*
  • *steampowered*/login*
  • *TextfieldPassword=*
  • *thepiratebay.org/login*
  • *torrentleech.org/*login*
  • *twitter.*/*direct_messages/new*
  • *twitter.*/*status*/update*
  • *twitter.com/sessions
  • *uploaded.to/*login*
  • *uploading.com/*login*
  • *vip-file.com/*/signin-do*
  • *vkontakte.ru/api.php
  • *vkontakte.ru/mail.php
  • *vkontakte.ru/wall.php
  • *webnames.ru/*user_login*
  • *what.cd/login*
  • *whcms*dologin*
  • *youporn.*/login*

It attempts to steal user credentials used in the following websites:

  • 1and1
  • 4shared
  • Alertpay
  • Bcointernacional
  • Bebo
  • BigString
  • Brazzers
  • Clave
  • Depositfiles
  • Dotster
  • DynDNS
  • Ebay
  • Email
  • Facebook
  • Fastmail
  • Fileserve
  • Filesonic
  • FLN-Password
  • FLN-UserName
  • Freakshare
  • Friendster
  • Gmail
  • Godaddy
  • Hackforums
  • Hotfile
  • IKnowThatGirl
  • Letitbit
  • LogMeIn
  • Mediafire
  • Megaupload
  • Message
  • Moneybookers
  • Moniker
  • Namecheap
  • Netflix
  • Netload
  • OfficeBanking
  • Passwd
  • PayPal
  • Runescape
  • Sendspace
  • Sms4file
  • Speedyshare
  • Steam
  • Thepiratebay
  • Torrentleech
  • Twitter
  • Uploaded
  • Uploading.com
  • Vip-file
  • Vkontakte
  • Webnames
  • Whatcd
  • Yahoo
  • YouPorn
  • YouTube

It monitors if browser accesses URLs with following strings to block the connection:

  • avast
  • avira
  • bitdefender
  • bullguard
  • clamav
  • comodo
  • emsisoft
  • eset
  • f-secure
  • fortinet
  • garyshood
  • gdatasoftware
  • heck.tc
  • iseclab
  • jotti
  • kaspersky
  • lavasoft
  • malwarebytes
  • mcafee
  • norman
  • norton
  • novirusthanks
  • nprotect
  • onecare.live
  • onlinemalwarescanner
  • pandasecurity
  • precisesecurity
  • sophos
  • sunbeltsoftware
  • symantec
  • threatexpert
  • trendmicro
  • virscan
  • virus
  • virusbuster
  • viruschief
  • virustotal
  • webroot

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

11.210.05

FIRST VSAPI PATTERN DATE:

14 Oct 2014

VSAPI OPR PATTERN File:

11.211.00

VSAPI OPR PATTERN Date:

15 Oct 2014

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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Restart in Safe Mode

[ 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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Screen Saver Pro 3.1 = "%Application Data%\ScreenSaverPro.scr"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • Tnrwrp = "%Application Data%\Microsoft\Tnrwrp.exe"

Step 5

Delete this registry key

[ 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\Applets
    • Paint

Step 6

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