Trojan.Win32.DOFOIL.AE

This Trojan 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 then deletes itself afterward.

As of this writing, the said sites are inaccessible.

It steals certain information from the system and/or the user.

It checks the operating system name of the affected computer.

Arrival Details

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

• %Application Data%\Microsoft\Windows\{random name}\{random name}.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It executes then deletes itself afterward.

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

• {generated hash based on system information}

Autostart Technique

This Trojan drops the following file(s) in the Windows User Startup folder to enable its automatic execution at every system startup:

• %User Startup%\{random name}.lnk

(Note: %User Startup% is the current user's Startup folder, which is usually C:\Windows\Profiles\{user name}\Start Menu\Programs\Startup on Windows 98 and ME, C:\WINNT\Profiles\{user name}\Start Menu\Programs\Startup on Windows NT, C:\Documents and Settings\{User name}\Start Menu\Programs\Startup on Windows 2003(32-bit), XP and 2000(32-bit), or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit), 10(64-bit).)

Process Termination

This Trojan terminates the following processes if found running in the affected system's memory:

• tcpview.exe
• Autoruns.exe
• IDAQ.exe
• OllyDbg.exe
• idaq.exe
• wireshark.exe
• idaq64.exe
• ProcessHacker.exe
• idaw64.exe
• idaw.exe
• procmon.exe
• procexp.exe
• Tcpview.exe

Download Routine

This Trojan connects to the following URL(s) to download its component file(s):

• http://{BLOCKED}6.co/zb/

As of this writing, the said sites are inaccessible.

Information Theft

This Trojan steals the following information:

• Computer Name
• Username
• System Volume Information

Other Details

This Trojan connects to the following URL(s) to check for an Internet connection:

• http://www.{BLOCKED}si.com/ncsi.txt

It checks the operating system name of the affected computer if it is any of the following:

• Windows Vista or a latter version is required for it to run.

It does the following:

• Extracts Window Class Names and terminates the process if it matches a hash from its list of hashes.
• Checks for the presence of known sandbox IDs in the following registry keys:
  • HKEY_LOCAL_MACHINE\SYSTEM\CurrentControLSet\Enum\SCSI
  where the sandbox IDs could be any of the following:
  • qemu
  • virtual
  • vmware
  • xen
• It checks for the following DLL or modules if existing:
  • sbiedll
  If found, it terminates itself
• It deletes traces of internet access by deleting the following files:
  • {malware name}:Zone Identifier

It does not proceed to its malicious routine if it detects that it is being debugged.

It adds the following scheduled tasks:

• • Task Name: Opera scheduled Autoupdate {hardcoded number}
  • Trigger: At 12:00 AM on 11/30/1999 - After triggered, repeat every 10 minutes indefinitely.
  • Action: %Application Data%\Microsoft\Windows\{random name}\{random name}.exe

(Note: %Application Data% is the current user's Application Data folder, which is usually C:\Documents and Settings\{user name}\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Roaming on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)