X2KM_HELMINTH.A

 Analysis by: Jennifer Gumban

 PLATFORM:

Windows 7

 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:

Via email


This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

  TECHNICAL DETAILS

File Size:

177,152 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

02 Sep 2016

Arrival Details

This Trojan arrives as an attachment to email messages spammed by other malware/grayware or malicious users.

Installation

This Trojan drops the following files:

    • %Public%\Libraries\{filename}.vbs - detected as VBS_HELMINTH.A
    • %Public%\Libraries\{filename}.ps1 - detected as VBS_HELMINTH.A


    The files' content are from base64 encoded values from worksheet "Incompatible"

It creates the following folders:

    • %Public%\Libraries\up
    • %Public%\Libraries\dn
    • %Public%\Libraries\tp

    The folders are created if "%Public%\Libraries\{filename}.vbs" does not exist

Other Details

This Trojan requires the following additional components to properly run:

  • %Public%\Libraries\{filename}.vbs

It does the following:

  • It creates the following scheduled task:
    • Name: GoogleUpdateTaskMachineUI
    • Trigger: Every 3 minutes
    • Action: Execute "%Public%\Libraries\{filename}.vbs"

This is the Trend Micro detection for Microsoft Word documents that are compromised through the insertion of a malicious macro.

  SOLUTION

Minimum Scan Engine:

9.800

FIRST VSAPI PATTERN FILE:

12.752.02

FIRST VSAPI PATTERN DATE:

02 Sep 2016

VSAPI OPR PATTERN File:

12.753.00

VSAPI OPR PATTERN Date:

03 Sep 2016

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

Delete the Scheduled Tasks added by this malware/grayware

[ Learn More ]

To delete the added Scheduled Task file:

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

  1. Open the Windows Scheduled Tasks. To do this, click Start>Programs>Accessories>System Tools>Scheduled Tasks.
  2. Double-click on a .JOB file.
  3. Check if the malware path and file name exists in the .JOB file. To do this, check the value in the Run field.
  4. If found, select the .JOB file then press SHIFT+DELETE to permanently delete the file.
  5. Repeat the steps above for the remaining .JOB files.

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

  1. Open the Windows Task Scheduler. To do this:
    • On Windows Vista, Windows 7, and Windows Server 2008, click Start, type taskschd.msc in the Search input field, then press Enter.
    • On Windows 8, Windows 8.1, and Windows Server 2012, right-click on the lower left corner of the screen, click Run, type taskschd.msc, then press Enter.
  2. In the left panel of the Task Scheduler Window, click Task Scheduler Library.
  3. In the upper-middle panel, click a Task.
  4. In the lower middle panel, click the Actions tab
  5. Check if the malware path and file name exists in the task. To do this, check the value in the Details column under the Actions tab.
  6. If found, select the task and press DELETE and click Yes to delete the task.
  7. Repeat the steps above for the remaining tasks.

Step 4

Remove malware/grayware files dropped/downloaded by X2KM_HELMINTH.A. (Note: Please skip this step if the threats listed below have already been removed.)

     
    • VBS_HELMINTH.A

Step 5

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. DATA_GENERIC
  • In the Look In drop-down list, select My Computer, then press Enter.
  • Once located, select the folder then press SHIFT+DELETE to permanently delete the folder.
  • Repeat steps 2 to 4 for the remaining folders:
      DATA_GENERIC
    *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:

    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:
      DATA_GENERIC
    3. Once located, select the file then press SHIFT+DELETE to permanently delete the folder.
    4. Repeat steps 2-3 for the remaining folders:
        DATA_GENERIC
      *Note: Read the following Microsoft page if these steps do not work on Windows 7.

    Step 6

    Scan your computer with your Trend Micro product to delete files detected as X2KM_HELMINTH.A. 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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