TROJ_INJECT.NSMTK

 Analysis by: Rheniel Rhay Ramos

 ALIASES:

Trojan.NSIS.Cayu.dvp (Kaspersky); Artemis!7D56C9886AC2 (McAfee); Packed.NSISPacker!g2 (Symantec)

 PLATFORM:

Windows

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

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware


This Trojan arrives as a component bundled with malware/grayware packages.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size:

1,183,910 bytes

Memory Resident:

No

Initial Samples Received Date:

07 Feb 2017

Payload:

Connects to URLs/IPs

Arrival Details

This Trojan arrives as a component bundled with malware/grayware packages.

Installation

This Trojan drops the following files:

  • %User Temp%\embed576997534.json
  • %User Temp%\embed821275402.json
  • %User Temp%\thedomains
  • %User Temp%\top-banner-.png
  • %User Temp%\about1017789822.html
  • %User Temp%\PIE.css
  • %User Temp%\backup_feed_CAF.js
  • %User Temp%\74ca38994f3ab19b51d51ffca5cda663.js
  • %User Temp%\74013fd427727eb949458445faaf86de.js
  • %User Temp%\uas4nUH6uM.r3tLq1ru0D
  • %User Temp%\nsq4BA1.tmp\System.dll

(Note: %User Temp% is the user's temporary folder, where it usually is C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Local\Temp on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.)

Other Details

This Trojan connects to the following website to send and receive information:

  • {BLOCKED}.{BLOCKED}.133.190:443

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

13.838.06

FIRST VSAPI PATTERN DATE:

12 Dec 2017

VSAPI OPR PATTERN File:

13.839.00

VSAPI OPR PATTERN Date:

13 Dec 2017

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

Identify and terminate files detected as TROJ_INJECT.NSMTK

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 4

Search and delete this folder

[ 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%\nsq4BA1.tmp

Step 5

Search and delete these files

[ Learn More ]
There may be some files 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 Temp%\embed576997534.json
  • %User Temp%\embed821275402.json
  • %User Temp%\thedomains
  • %User Temp%\top-banner-.png
  • %User Temp%\about1017789822.html
  • %User Temp%\PIE.css
  • %User Temp%\backup_feed_CAF.js
  • %User Temp%\74ca38994f3ab19b51d51ffca5cda663.js
  • %User Temp%\74013fd427727eb949458445faaf86de.js
  • %User Temp%\uas4nUH6uM.r3tLq1ru0D

Step 6

Scan your computer with your Trend Micro product to delete files detected as TROJ_INJECT.NSMTK. 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 the following Trend Micro Support pages for more information:


Did this description help? Tell us how we did.