TROJ_PONMOCUP.TN

 Analysis by: Sammy Chua

 ALIASES:

VirTool:Win32/Obfuscator.AFX (Microsoft); Troj/Ponmocup-O (Sophos); W32/Ponmocup.GG!tr (Fortinet)

 PLATFORM:

Windows

 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

This Trojan may arrive bundled with malware packages as a malware component. It may be dropped by other malware.

  TECHNICAL DETAILS

File Size:

94,208 bytes

File Type:

DLL

Memory Resident:

Yes

Initial Samples Received Date:

26 Jan 2015

Arrival Details

This Trojan may arrive bundled with malware packages as a malware component.

It may be dropped by other malware.

NOTES:

This Trojan requires the following information on the affected machine where it is installed in order to decrypt and load its code which contains the intended routine:

  • Volume serial number of %System Root% folder
  • Creation time of %System% folder
  • Creation time of %System Root%\System Volume Information folder
  • GUID of system root folder

The following export function of this Trojan is used by another malware:

  • WJNGDZMXV

After verifying the infected system, it executes the following routines:

  • Reads and decrypts the contents of the registry key:
    HKEY_LOCAL_MACHINE\Software\Haryhi\Yzhxvsth = "encrypted hex codes}"
  • Executes the decrypted code containing malicious instructions

The malicious instructions based from the submitted registry are the following:

  • Adds mutex Global\ilcvcr to ensure that only one of its copies runs at any one time
  • Terminates processes mrt.exe, msascui.exe, Msseces.exe if found running in the infected system
  • Modifies the following registry entries:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MsMpSvc
    Start = 4
    (Note: The default value data of the said registry entry is 2)
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Windefend
    Start = 4
    (Note: The default value data of the said registry entry is 2.)
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\wscsvc
    Start = 4
    (Note: The default value data of the said registry entry is 2.)
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender
    DisableAntiSpyware = 1
    (Note: The default value data of the said registry entry is 0.)
  • Reads the contents of the following registry entry:

    HKEY_LOCAL_MACHINE\Software\Microsoft\Multimedia
    {number} = "{hex strings}"
  • Reads and decrypts the contents and execute the decrypted code of the following registry entry:

    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings
    {number} = {encrypted hex codes}

  SOLUTION

Minimum Scan Engine:

9.700

FIRST VSAPI PATTERN FILE:

11.426.05

FIRST VSAPI PATTERN DATE:

21 Jan 2015

VSAPI OPR PATTERN File:

11.427.00

VSAPI OPR PATTERN Date:

22 Jan 2015

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

Scan your computer with your Trend Micro product and note files detected as TROJ_PONMOCUP.TN

Step 4

Restart in Safe Mode

[ Learn More ]

Step 5

Search and delete the files detected as TROJ_PONMOCUP.TN

*Note: Some component files may be 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.

To stop the malware/grayware from running when certain files are opened:

For Windows 2000, Windows XP, and Windows Server 2003:

  1. Right-click Start then click Search....
  2. In the File name* input box, type the name of the file that was detected earlier.
  3. In the Look In drop-down list, select My Computer then press Enter.
  4. Once located, select the file then press SHIFT+DELETE to delete it.
    *Note: The file name input box title varies depending on the Windows version (e.g. Search for files or folders named or All or part of the file name.).

For Windows Vista, Windows 7, Windows Server 2008, Windows 8, Windows 8.1, and Windows Server 2012 (R2):

  1. Open a Windows Explorer window.
    • For Windows Vista, 7, and Server 2008 users, click Start>Computer.
    • For Windows 8, 8.1, and Server 2012 users, right-click on the lower left corner of the screen,then click File Explorer.
  2. In the Search Computer/This PC input box, type the name of the file that was detected earlier.
  3. Once located, select the file then press SHIFT+DELETE to delete it.
    *Note: Read the following Microsoft page if these steps do not work on Windows 7.

Step 6

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_PONMOCUP.TN. 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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