WORM_KELIHOS.TSH

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It executes commands from a remote malicious user, effectively compromising the affected system. It connects to a website to send and receive information.

Arrival Details

This worm arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

Installation

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

• {random directory}\{random file name 1}

It drops the following files:

• {Drive Letter}:\Shortcut to {random file name 2}.lnk
• {Drive Letter}:\{Folder name}.lnk - points to malware copy {Drive Letter}:\{random file name 2}.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 parameter 1}{random parameter 2} = "{random directory}\{random file name 1}"

Other System Modifications

This worm adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
DefaultCompressedRecord = "{random value}"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
RecordModifiedMax = "{random value}=="

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
FlagsModifiedValid = "0"

HKEY_CURRENT_USER\Software\TansuTCP
ActiveModifiedTheme = "{random value}"

HKEY_CURRENT_USER\Software\TansuTCP
SizeCompletedValid = "{random value}=="

HKEY_CURRENT_USER\Software\TansuTCP
InfoPlayedCurrent = "0"

Propagation

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

• {Drive Letter}:\{random file name 2}.exe

Backdoor Routine

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

• Request spam email messages structure and template
• Send spam email messages
• Send stolen information
• Get operating system information
• Get drive information
• List running processes
• Download and execute arbitrary files
• Update server with a list of compromised computers
• Manage registry
• Download updated copy of itself

It connects to the following websites to send and receive information:

• http://{BLOCKED}.{BLOCKED}.92.60/index.htm
• http://{BLOCKED}.{BLOCKED}.92.60/install.htm
• http://{BLOCKED}.{BLOCKED}.29.191/index.htm
• http://{BLOCKED}.{BLOCKED}.29.191/search.htm
• http://{BLOCKED}.{BLOCKED}.99.41/default.htm
• http://{BLOCKED}.{BLOCKED}.99.41/index.htm
• http://{BLOCKED}.{BLOCKED}.99.47/default.htm
• http://{BLOCKED}.{BLOCKED}.99.47/index.htm
• http://{BLOCKED}.{BLOCKED}.26.213/home.htm
• http://{BLOCKED}.{BLOCKED}.26.213/install.htm
• http://{BLOCKED}.{BLOCKED}.41.85/defaul .htm
• http://{BLOCKED}.{BLOCKED}.41.85/install.htm
• http://{BLOCKED}.{BLOCKED}.50.176/install.htm
• http://{BLOCKED}.{BLOCKED}.50.176/online.htm
• http://{BLOCKED}.{BLOCKED}.50.176/search.htm
• http://{BLOCKED}.{BLOCKED}.50.176/setup.htm
• http://{BLOCKED}.{BLOCKED}.199.75/main.htm
• http://{BLOCKED}.{BLOCKED}.199.75/search.htm
• http://{BLOCKED}.{BLOCKED}.252.113/online.htm
• http://{BLOCKED}.{BLOCKED}.252.113/setup.htm
• http://{BLOCKED}.{BLOCKED}.101.47/default.htm
• http://{BLOCKED}.{BLOCKED}.101.47/start.htm
• http://{BLOCKED}.{BLOCKED}.245.128/online.htm
• http://{BLOCKED}.{BLOCKED}.245.128/welcome.htm
• http://{BLOCKED}.{BLOCKED}.43.230/default.htm
• http://{BLOCKED}.{BLOCKED}.43.230/file.htm
• http://{BLOCKED}.{BLOCKED}.79.46/default.htm
• http://{BLOCKED}.{BLOCKED}.79.46/start.htm
• http://{BLOCKED}.{BLOCKED}.152.225/default.htm
• http://{BLOCKED}.{BLOCKED}.152.225/online.htm
• http://{BLOCKED}.{BLOCKED}.43.85/search.htm
• http://{BLOCKED}.{BLOCKED}.43.85/index.htm
• http://{BLOCKED}.{BLOCKED}.65.82/welcome.htm
• http://{BLOCKED}.{BLOCKED}.65.82/default.htm

Information Theft

This worm attempts to steal stored account information used in the following installed File Transfer Protocol (FTP) clients or file manager software:

• 32BitFTP
• 3D-FTP
• ALFTP
• AceBIT
• BitKinex
• BlazeFtp
• BulletProof FTP
• ClassicFTP
• CoffeeCup Software
• Core FTP
• Cyberduck
• DeluxeFTP
• Directory Opus
• EasyFTP
• FTPNow
• FarManager
• FastStone FTP
• FFFTP
• FileZilla
• FlashFXP
• Fling FTP
• FreshFTP
• FTPGetter
• FTP Commander
• FTP Control
• FTP Explorer
• FTP Navigator
• FTP Surfer
• FTPRush
• FTPShell
• GlobalSCAPE CuteFTP 6 Home
• GlobalSCAPE CuteFTP 6 Professional
• GlobalSCAPE CuteFTP
• GlobalSCAPE CuteFTP 7 Home
• GlobalSCAPE CuteFTP 7 Professional
• GlobalSCAPE CuteFTP 8 Home
• GlobalSCAPE CuteFTP 8 Professional
• GlobalSCAPE CuteFTP Lite
• GlobalSCAPE CuteFTP Pro
• KiTTY
• LeapWare
• LeechFTP
• LinasFTP
• MAS-Soft FTPInfo
• My FTP
• NetDrive
• NetSarang
• NexusFile
• NovaFTP
• NppFTP
• PuTTY
• Quick FTP
• Robo-FTP
• SecureFX
• SmartFTP
• SoftX FTP Client
• Total Commander
• TurboFTP
• UltraFXP
• WebDrive
• WebSitePublisher
• WinFTP
• WinSCP
• WS_FTP

It gathers the following account information from any of the mentioned File Transfer Protocol (FTP) clients or file manager software:

• Server Name
• User Name
• Password
• Directory
• Port

It attempts to get stored information such as user names, passwords, and hostnames from the following browsers:

• Bromium
• ChromePlus
• Chromium
• Comodo
• CoolNovo
• Epic Browser
• Google Chrome
• K-Meleon
• Nichrome
• Rockmelt
• Yandex

NOTES:

This worm modifies its file attributes to Read-only and Hidden after execution.

It drops copies of itself as {random file name 1} with the following file names in different directories:

• acrord32
• agent
• ati2evxx
• avguard
• batch
• block
• ccapp
• ccevtmgr
• ccsetmgr
• convert
• decompile
• defwatch
• download
• em_exec
• explorer
• extract
• ezsp_px
• firefox
• gearsec
• hkcmd
• htpatch
• ielowutil
• ieuser
• iexplore
• igfxtray
• isuspm
• jucheck
• jusched
• khalmnpr
• klwtblfs
• launch
• lsass
• lucoms
• mcshield
• mcvsescn
• msascui
• mscorsvw
• mspmspsv
• naprdmgr
• navapsvc
• nprotect
• ntvdm
• nvsvc32
• nvxdsync
• pctspk
• pdvddxsrv
• point32
• qbw32
• qttask
• rename
• rundll32
• services
• sidebar
• spoolsv
• svchost
• taskman
• terraria
• toaster
• trustedinstaller
• umodrive
• unhide
• unpack
• unzip
• update
• upgrade
• uptime
• vsmon
• webscanx
• winlogon
• wisptis
• wmpnetwk
• wmpnscfg
• zcfgsvc

The dropped copy, {random file name 2} in removable drives can be any of the following:

• click
• game
• hentai
• installer
• password
• porn
• run
• sas
• screensaver

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.

The auto-run registry, {random parameter 1} can be any of the following:

• Network
• Time
• CrashReport
• Database
• Icon
• Desktop
• Tray
• Video
• Media

The auto-run registry, {random parameter 2} can be any of the following:

• Checker
• Informer
• Notifyer
• Saver
• Updater
• Verifyer

For example:

• NetworkVerifyer
• TrayNotifyer
• CrashReportUpdater

It monitors network traffic to acquire data from E-mail and FTP accounts using the following strings:

• AUTH_PLAIN
• Authorization
• Basic
• CONNECT
• PASS
• USER
• pop3_smtp

It exchanges encrypted messages with a remote server via HTTP protocol (TCP port 80). It uses the following crafted User-Agent when communicating with the remote host:

• Mozilla/5.0 (Windows NT 5.1) Gecko/20100101 Firefox/14.0 Opera/12.0
• Opera/9.80 (Windows NT 5.1; U; zh-sg) Presto/2.9.181 Version/12.00
• Opera/9.80 (Windows NT 6.1; U; es-ES) Presto/2.9.181 Version/12.00
• Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.0) Opera 12.14
• Mozilla/5.0 (Windows NT 6.0; rv:2.0) Gecko/20100101 Firefox/4.0 Opera 12.14
• Opera/9.80 (Windows NT 6.0) Presto/2.12.388 Version/12.14
• Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_7; da-dk) AppleWebKit/533.21.1 (KHTML, like Gecko) Version/5.0.5 Safari/533.21.1
• Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; de-at) AppleWebKit/533.21.1 (KHTML, like Gecko) Version/5.0.5 Safari/533.21.1
• Mozilla/5.0 (iPad; CPU OS 5_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko ) Version/5.1 Mobile/9B176 Safari/7534.48.3
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_3) AppleWebKit/534.55.3 (KHTML, like Gecko) Version/5.1.3 Safari/534.53.10
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10_6_8) AppleWebKit/537.13+ (KHTML, like Gecko) Version/5.1.7 Safari/534.57.2
• Mozilla/5.0 (iPad; CPU OS 6_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A5355d Safari/8536.25
• Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; chromeframe/12.0.742.112)
• Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0; SLCC2; Media Center PC 6.0; InfoPath.3; MS-RTC LM 8; Zune 4.7)
• Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 7.1; Trident/5.0)
• Mozilla/5.0 (Windows; U; MSIE 9.0; Windows NT 9.0; en-US)
• Mozilla/1.22 (compatible; MSIE 10.0; Windows 3.1)
• Mozilla/4.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/5.0)
• Mozilla/5.0 (compatible; MSIE 10.0; Macintosh; Intel Mac OS X 10_7_3; Trident/6.0)
• Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/4.0; InfoPath.2; SV1; .NET CLR 2.0.50727; WOW64)
• Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/5.0)
• Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/6.0)
• Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; WOW64; Trident/6.0)
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (Windows NT 5.0; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (Windows NT 5.1; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (Windows NT 5.1; rv:21.0) Gecko/20130331 Firefox/21.0
• Mozilla/5.0 (Windows NT 5.1; rv:21.0) Gecko/20130401 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; rv:21.0) Gecko/20130328 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; rv:21.0) Gecko/20130401 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20130330 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20130331 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20130401 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.2; rv:21.0) Gecko/20130326 Firefox/21.0
• Mozilla/5.0 (X11; Linux i686; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:21.0) Gecko/20100101 Firefox/21.0
• Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:21.0) Gecko/20130331 Firefox/21.0
• Mozilla/5.0 (Windows NT 6.1; rv:22.0) Gecko/20130405 Firefox/22.0
• Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:22.0) Gecko/20130328 Firefox/22.0
• Mozilla/5.0 (Windows NT 6.2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1464.0 Safari/537.36
• Mozilla/5.0 (Windows NT 6.2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1467.0 Safari/537.36
• Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1468.0 Safari/537.36
• Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.2 Safari/537.36
• Mozilla/5.0 (compatible; MSIE 9.0; AOL 9.7; AOLBuild 4343.19; Windows NT 6.1; WOW64; Trident/5.0; FunWebProducts)
• Mozilla/5.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; Acoo Browser 1.98.744; .NET CLR 3.5.30729)

It also attempts to steal information from %Application Data%\Bitcoin\wallet.dat.

It sends spammed email messages using Simple Mail Transfer Protocol (SMTP) connection.

It also has the capability to get a new list of IP addresses from its C&C server. The list of addresses may change depending on the malware author.

It does not have rootkit capabilities.

It does not exploit any vulnerability.