TSPY_EMOTET.TTHBBGH

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

It connects to a website to send and receive information.

Arrival Details

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

• %AppDataLocal%\Microsoft\Windows\{string 1}{string 2}.exe - drops the file here if it has no admin privileges
• %System%\{string 1}{string 2}.exe - drops the file here if it has admin privileges
  where {string 1} and {string 2} is a combination of any of the following strings:
  • Allow
  • Appointment
  • Bat
  • Bthhf
  • Cci
  • Chunk
  • Clu
  • Contact
  • Crash
  • Crs
  • Dac
  • Dcard
  • Def
  • Dpi
  • Encoding
  • Express
  • Extractor
  • Fill
  • Fix
  • Gabriola
  • Hawaii
  • Hgfs
  • Keydef
  • Link
  • Loop
  • Lsa
  • Lua
  • Mbae
  • Model
  • Monet
  • Month
  • Msi
  • Outlined
  • Overload
  • Partition
  • Pivot
  • Plane
  • Playlist

(Note: %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

• M{hash of full file path}
• Global\I{volume serial number}
• Global\M{volume serial number}

Autostart Technique

This Trojan Spy registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\{string 1}{string 2}
ImagePath = "%System%\{string 1}{string 2}.exe"
where {string 1} and {string 2} is the same name as the drop file

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{string 1}{string 2} = "%AppDataLocal%\Microsoft\Windows\{string 1}{string 2}.exe"

Other System Modifications

This Trojan Spy deletes the following files:

• %AppDataLocal%\Microsoft\Windows\{string 1}{string 2}.exe (deletes the file here if it has no admin privileges)
• %System%\{string 1}{string 2}.exe (deletes the file here if it has admin privileges)
  where {string 1} and {string 2} is a combination of any of the following strings:
  • agent
  • app
  • audio
  • bio
  • bits
  • cache
  • card
  • cart
  • cert
  • com
  • crypt
  • dcom
  • defrag
  • device
  • dhcp
  • dns
  • event
  • evt
  • flt
  • gdi
  • group
  • help
  • home
  • host
  • info
  • iso
  • launch
  • log
  • logon
  • lookup
  • man
  • math
  • mgmt
  • msi
  • ncb
  • net
  • nv
  • nvidia
  • proc
  • prop
  • prov
  • provider
  • reg
  • rpc
  • screen
  • search
  • sec
  • server
  • service
  • shed
  • shedule
  • spec
  • srv
  • storage
  • svc
  • sys
  • system
  • task
  • time
  • video
  • view
  • win
  • window
  • wlan
  • wmi

(Note: %AppDataLocal% is the Application Data folder found in Local Settings, where it is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local 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.. %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Backdoor Routine

This Trojan Spy connects to the following websites to send and receive information:

• http://{BLOCKED}.{BLOCKED}.152.123:4143/
• http://{BLOCKED}.{BLOCKED}.173.247:4143/
• http://{BLOCKED}.{BLOCKED}.81.235:8080/

Information Theft

This Trojan Spy gathers the following data:

• Machine Name
• System Locale
• OS Version
• Running Processes

Other Details

This Trojan Spy does the following:

• It will create a startup service if it has admin privileges, otherwise it will only create an autorun entry in the registry.
• It is capable of downloading different modules from the C&C server.