TROJ_SULUNCH.VI

 Modified by: Jaime Benigno Reyes

 ALIASES:

n32/VBInject.gen!MJ (Microsoft); .Win32.FakeFolder.h (Kaspersky)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: Yes

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware, Downloaded from the Internet

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 may be downloaded by other malware/grayware from remote sites.

It does not have any propagation routine.

It does not have any backdoor routine.

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

  TECHNICAL DETAILS

File Size:

Varies

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

29 Aug 2014

Payload:

Downloads files

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.

It may be downloaded by the following malware/grayware from remote sites:

  • BKDR_ANDROM.WEY

It may be downloaded from the following remote sites:

  • http://{BLOCKED}.{BLOCKED}.137.91/images/0/saner.exe

Installation

This Trojan drops the following component file(s):

  • %User Temp%\{random}.tmp\starter.bat - deleted afterwards
  • %User Temp%\{random}.tmp\wget.exe - moved to %Windows%\AppUpdate afterwards
  • %User Temp%\{random}.tmp\updater.exe - also detected as TROJ_SULUNCH.VI, moved to %Windows%\AppUpdate afterwards
  • %User Temp%\{random}.tmp\waitfor.exe - moved to %Windows%\AppUpdate afterwards
  • %User Temp%\{random}.tmp\elevate.exe - deleted afterwards
  • %User Temp%\ztmp\t{random number}.exe
  • %User Temp%\ztmp\t{random number}.bat
  • %Windows%\AppUpdate\wget.exe
  • %Windows%\AppUpdate\updater.exe - also detected as TROJ_SULUNCH.VI
  • %Windows%\AppUpdate\waitfor.exe

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

It creates the following folders:

  • %User Temp%\ztmp
  • %User Temp%\afolder
  • %User Temp%\{random}.tmp - deleted afterwards
  • %Windows%\AppUpdate

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

Autostart Technique

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

HKEY_LOCAL_MACHINE\Software\Microsoft\
Windows\CurrentVersion\Run
AppUpdate = "%Windows%\AppUpdate\updater.exe"

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Download Routine

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

  • http://{BLOCKED}ad1.fileshare.pw/32.exe - detected as TROJ_SULUNCH.VK
  • http://{BLOCKED}ad1.fileshare.pw/update/32.exe - detected as TROJ_KRYPTIK.DWN
  • http://{BLOCKED}ad1.fileshare.pw/update/updater_32_1.exe - detected as TROJ_KRYPTIK.DWN
  • http://{BLOCKED}ad1.hyips.pw/update.exe (inaccessible)
  • http://{BLOCKED}ad1.hyips.pw/update/update.exe (inaccessible)
  • http://{BLOCKED}ad1.microliteupdate.net/update.exe (inaccessible)
  • http://{BLOCKED}ad1.microliteupdate.net/update/update.exe (inaccessible)
  • http://{BLOCKED}ad1.onlinefile.pw/32.exe (inaccessible)
  • http://{BLOCKED}ad1.onlinefile.pw/update/32.exe (inaccessible)
  • http://{BLOCKED}ad1.onlinefile.pw/update/updater_32_1.exe (inaccessible)

It saves the files it downloads using the following names:

  • %User Temp%\32.exe
  • %User Temp%\update.exe
  • %User Temp%\updater_32_1.exe

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

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

NOTES:

It does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

11.116.03

FIRST VSAPI PATTERN DATE:

29 Aug 2014

VSAPI OPR PATTERN File:

11.117.00

VSAPI OPR PATTERN Date:

30 Aug 2014

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

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

Remove malware/grayware files that dropped/downloaded TROJ_SULUNCH.VI. (Note: Please skip this step if the threats listed below have already been removed.)

  • BKDR_ANDROM.WEY

Step 4

Remove the malware/grayware file dropped/downloaded by TROJ_SULUNCH.VI. (Note: Please skip this step if the threat(s) listed below have already been removed.)

  • TROJ_SULUNCH.VK
  • TROJ_KRYPTIK.DWN

Step 5

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_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
    • AppUpdate = "%Windows%\AppUpdate\updater.exe"

Step 6

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Temp%\ztmp
  • %User Temp%\afolder
  • %Windows%\AppUpdate

Step 7

Scan your computer with your Trend Micro product to delete files detected as TROJ_SULUNCH.VI. 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.


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