TSPY_EMOTET.TTIBBHY

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 certain websites to send and receive information. However, as of this writing, the said sites are inaccessible. It deletes the initially executed copy of itself.

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
  or %AppDataLocal%\Microsoft\Windows\{random string}.exe
• %System%\{string 1}{string 2}.exe ← drops the file here if it has admin privileges
  or %System%\{random string}.exe
  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.)

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

• Global\I{volume serial number}
• M{hash of full file path}
• 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\{random string}
ImagePath = %System%\{random string}.exe

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
{random string} = %AppdataLocal%\Microsoft\Windows\{random string}.exe

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

Information Theft

This Trojan Spy gathers the following data:

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

Other Details

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

• http://{BLOCKED}.{BLOCKED}.33.122:20/
• http://{BLOCKED}.{BLOCKED}.170.139:4143/

It 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.

However, as of this writing, the said sites are inaccessible.

It deletes the initially executed copy of itself