arrow_back
search
close

TROJ_SIREFEF.SMH

October 18, 2013
 ALIASES:

Trojan:Win32/Otran (Microsoft); Generic VB.aaab (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Jorik.Vobfus.lgf (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Gen:Variant.Zusy.2786 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


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.

  TECHNICAL DETAILS

File Size:

577,536 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

20 Jul 2012

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.

Autostart Technique

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

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /R"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /Q"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /M"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /N"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /T"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /U"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /u"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /q"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /s"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /o"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /X"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /a"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /P"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /f"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /S"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /F"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /d"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /K"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /A"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /c"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /Y"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /r"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /C"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /V"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /w"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /n"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /v"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /x"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /J"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /t"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /k"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /Z"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /p"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /W"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /j"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /y"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /h"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /m"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /e"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /B"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /D"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /O"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /E"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /g"

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
bepaw = "%User Profile%\bepaw.exe /b"

It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
services\.afd

Other System Modifications

This Trojan deletes the following files:

  • %User Profile%\2eaz.exe

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\Software\Classes\
Interface\{58633341-5816-2bc7-2251-cb7edbdd0cf8}

HKEY_CURRENT_USER\Software\223f9631

It adds the following registry entries:

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

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\
Microsoft\Windows\WindowsUpdate\
AU
NoAutoUpdate = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
Interface\{58633341-5816-2bc7-2251-cb7edbdd0cf8}
u = "bc"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\.afd
Type = "1"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\.afd
Start = "3"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\.afd
ImagePath = "\?"

HKEY_CURRENT_USER\Software\223f9631
u = "bc"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Direct3D\MostRecentApplication
Name = "3eaz.exe"

(Note: The default value data of the said registry entry is vfp6.exe.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Direct3D\MostRecentApplication
Name = "X"

(Note: The default value data of the said registry entry is vfp6.exe.)

Dropping Routine

This Trojan drops the following files:

  • %User Profile%\html.html
  • U
  • L
  • ACPI#PNP0303#2&da1a3ff&0\L\enixkeeo
  • ACPI#PNP0303#2&da1a3ff&0\@
  • @
  • X

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://newsblog.{BLOCKED}k.to/a.txt

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

Step 1

Before doing any scans, Windows XP, Windows Vista, and Windows 7 users must disable System Restore to allow full scanning of their computers.

Step 2

Restart in Safe Mode

[ Learn More ]

Step 3

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services
    • .afd
  • In HKEY_LOCAL_MACHINE\Software\Classes\Interface
    • {58633341-5816-2bc7-2251-cb7edbdd0cf8}
  • In HKEY_CURRENT_USER\Software
    • 223f9631

Step 4

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /R"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /Q"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /M"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /N"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /T"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /U"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /u"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /q"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /s"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /o"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /X"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /a"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /P"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /f"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /S"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /F"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /d"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /K"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /A"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /c"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /Y"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /r"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /C"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /V"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /w"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /n"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /v"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /x"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /J"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /t"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /k"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /Z"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /p"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /W"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /j"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /y"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /h"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /m"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /e"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /B"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /D"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /O"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /E"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /g"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
    • bepaw = "%User Profile%\bepaw.exe /b"
  • In HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • ShowSuperHidden = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU
    • NoAutoUpdate = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Interface\{58633341-5816-2bc7-2251-cb7edbdd0cf8}
    • u = "bc"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\.afd
    • Type = "1"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\.afd
    • Start = "3"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\.afd
    • ImagePath = "\?"
  • In HKEY_CURRENT_USER\Software\223f9631
    • u = "bc"

Step 5

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Direct3D\MostRecentApplication
    • From: Name = "3eaz.exe"
      To: Name = ""vfp6.exe""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Direct3D\MostRecentApplication
    • From: Name = "X"
      To: Name = ""vfp6.exe""

Step 6

Search and delete these components

[ Learn More ]
There may be some components that are hidden. Please make sure you check the Search Hidden Files and Folders checkbox in the "More advanced options" option to include all hidden files and folders in the search result.
  • %User Profile%\html.html
  • U
  • L
  • ACPI#PNP0303#2&da1a3ff&0\L\enixkeeo
  • ACPI#PNP0303#2&da1a3ff&0\@
  • @
  • X

Step 7

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_SIREFEF.SMH. If the detected files have already been cleaned, deleted, or quarantined by your Trend Micro product, no further step is required. You may opt to simply delete the quarantined files. Please check this Knowledge Base page for more information.

Step 8

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Profile%\2eaz.exe


Did this description help? Tell us how we did.