WORM_DORKBOT.GU

This worm arrives via removable drives.

It is injected into all running processes to remain memory resident.

It drops copies of itself into all the removable drives connected to an affected system. It drops copies of itself in removable drives. These dropped copies use the names of the folders located on the said drives for their file names. It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

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

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

Arrival Details

This worm arrives via removable drives.

Installation

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

• %Application Data%\{random characters}.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 is injected into all running processes to remain memory resident.

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
{malware file name} = "{malware path and file name}"

Propagation

This worm creates the following folders in all removable drives:

• {drive letter}:\RECYCLER

It drops copies of itself into all the removable drives connected to an affected system.

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

• {drive letter}:\RECYCLER\{random characters}.exe

It drops copies of itself in removable drives. These dropped copies use the names of the folders located on the said drives for their file names.

It drops an AUTORUN.INF file to automatically execute the copies it drops when a user accesses the drives of an affected system.

The said .INF file contains the following strings:

[AutoRun]
;{garbage characters}
shellexecute=RECYCLER\{malware file name}.exe
;{garbage characters}
icon=shell32.dll,7
;{garbage characters}
shell\open\command=RECYCLER\{malware file name}.exe
;{garbage characters}
action=Open folder to view files
;{garbage characters}
shell\explore\command=RECYCLER\{malware file name}.exe
;{garbage characters}
useautoplay=1

It sends messages that contain links to sites hosting remote copies of itself using the following instant-messaging (IM) applications:

• MSN Messenger
• Pidgin
• Xchat
• MIRC
• Skype

Backdoor Routine

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

• Update itself
• Download other files
• Perfrom Slowloris, UDP, and SYN flooding
• Send MSN Messenger messages
• Insert iframe tags into HTML files
• Visit a Web page
• Create processes
• Block DNS
• Redirect domains
• Steal login credentials
• Log in to FTP sites

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

• {BLOCKED}v.{BLOCKED}n.cc
• {BLOCKED}v.{BLOCKED}c.cz
• {BLOCKED}up.{BLOCKED}idic.net
• {BLOCKED}p.{BLOCKED}k.net
• {BLOCKED}p.{BLOCKED}at.org
• {BLOCKED}p.{BLOCKED}s.in
• {BLOCKED}p.{BLOCKED}y.in

Rootkit Capabilities

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

NOTES:

It drops shortcut files pointing to the copy of itself in removable drives. These dropped LNK files use the names of the folders located on the said drives for their file names. It then sets the attributes of the original folders to Hidden to trick the user into clicking the LNK files. It monitors the Internet activities of the affected system to steal user credentials if the user visits Websites with the following strings:

• *&Password=*
• *&password=*
• *&txtPassword=*
• *.alertpay.*/*login.aspx
• *.moneybookers.*/*login.pl
• *:2083/login*
• *:2086/login*
• *FLN-Password=*
• *Passwd=*
• *TextfieldPassword=*
• *aol.*/*login.psp*
• *bigstring.*/*index.php*
• *dyndns*/account*
• *facebook.*/login.php*
• *fastmail.*/mail/*
• *fileserve.*/login*
• *gmx.*/*FormLogin*
• *google.*/*ServiceLoginAuth*
• *hackforums.*/member.php
• *login.live.*/*post.srf*
• *login.yahoo.*/*login*
• *loginUserPassword=*
• *login_password=*
• *megaupload.*/*login
• *no-ip*/login*
• *officebanking.cl/*login.asp*
• *pass=*
• *passwd=*
• *password=*
• *password]=*
• *paypal.*/webscr?cmd=_login-submit*
• *runescape*/*weblogin*
• *screenname.aol.*/login.psp*
• *secure.logmein.*/*logincheck*
• *service=youtube*
• *steampowered*/login*
• *twitter.com/sessions
• AOL
• AlertPay
• BigString
• DynDNS
• Email
• EmailName
• FLN-Password
• FLN-UserName
• Facebook
• Fastmail
• FileServe
• GMX
• Gmail
• Hackforums
• Live
• LogMeIn
• Megaupload
• Moneybookers
• NoIP
• OfficeBanking
• Passwd
• Password
• PayPal
• Runescape
• Steam
• TextfieldEmail
• TextfieldPassword
• Twitter
• Yahoo
• YouTube
• email
• login
• loginId
• loginUserName
• loginUserPassword
• login_email
• login_password
• pass
• passwd
• password
• quick_password
• quick_username
• screenname
• session[password]
• session[username_or_email]
• txtEmail
• txtPassword
• user
• username

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

• AOL
• AlertPay
• BigString
• DynDNS
• Facebook
• Fastmail
• FileServe
• Fileserve
• GMX
• Gmail
• Google
• Hack Forums
• Hackforums
• Live
• LogMeIn
• Megaupload
• Money Bookers
• Moneybookers
• NoIP
• Office Banking
• OfficeBanking
• PayPal
• Paypal
• Runescape
• Steam
• Steam Powered
• Twitter
• Twitter.com
• Yahoo
• YouTube

It blocks access to Websites with the following strings:

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

It hooks the following APIs to aid its routines:

• NtEnumerateValueKey
• NtQueryDirectoryFile
• NtResumeThread
• LdrLoadDll
• CreateFileA
• CreateFileW
• MoveFileW
• CopyFileA
• CopyFileW
• MoveFileA
• RegCreateKeyExW
• RegCreateKeyExA
• HttpSendRequestA
• InternetWriteFile
• HttpSendRequestW
• getaddrinfo
• send

It may also disable the user from using the following applications:

• ipconfig.exe
• verclsid.exe
• regedit.exe
• rundll32.exe
• cmd.exe
• regsvr32.exe