Analysis by: Jennifer Gumban
 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: Downloaded from the Internet

As of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size: 99,410 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 25 Jun 2017
Payload: Connects to URLs/IPs

Arrival Details

This malware arrives via the following means:

  • Sundown-Pirate Exploit Kit

Installation

This Trojan drops a copy of itself in the following folders using different file names:

  • %Application Data%\Microsoft\{random folder}\{random filename}.exe

(Note: %Application Data% is the Application Data folder, where it usually is C:\Documents and Settings\{user name}\Application Data on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name}\AppData\Roaming 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.)

It drops the following file(s)/component(s):

  • %User Temp%\MattStarlight.dat
  • %User Temp%\crate.dll
  • %User Temp%\{random folder}\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.)

Download Routine

This Trojan accesses the following websites to download files:

  • http://{BLOCKED}.{BLOCKED}.36.91

Trend Micro detects the dowloaded file as:

  • TSPY_ZYKLON.C

As of this writing, the said sites are inaccessible.

  SOLUTION

Minimum Scan Engine: 9.850
FIRST VSAPI PATTERN FILE: 13.532.05
FIRST VSAPI PATTERN DATE: 14 Jul 2017
VSAPI OPR PATTERN File: 13.533.00
VSAPI OPR PATTERN Date: 15 Jul 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

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

     
    • TSPY_ZYKLON.C

Step 4

Scan your computer with your Trend Micro product to clean files detected as TROJ_SMOKELOAD.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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