Analysis by: Jeanne Jocson

ALIASES:

Trojan.MSIL.Miner.aid (Kaspersky)

 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

This Trojan uses Windows Task Scheduler to create a scheduled task that executes the dropped copy.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 112,640 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 24 Jan 2017
Payload: Connects to URLs/IPs

Installation

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

  • %All Users Profile%\UpdateService\UpdateService.exe

(Note: %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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 component file(s):

  • %Application Data%\AppCache\1\cygcom_err-2.dll
  • %Application Data%\AppCache\1\cygcrypto-1.0.0.dll
  • %Application Data%\AppCache\1\cygcurl-4.dll
  • %Application Data%\AppCache\1\cyggcc_s-1.dll
  • %Application Data%\AppCache\1\cyggssapi_krb5-2.dll
  • %Application Data%\AppCache\1\cygiconv-2.dll
  • %Application Data%\AppCache\1\cygidn-11.dll
  • %Application Data%\AppCache\1\cygintl-8.dll
  • %Application Data%\AppCache\1\cygk5crypto-3.dll
  • %Application Data%\AppCache\1\cygkrb5-3.dll
  • %Application Data%\AppCache\1\cygkrb5support-0.dll
  • %Application Data%\AppCache\1\cyglber-2-4-2.dll
  • %Application Data%\AppCache\1\cygldap-2-4-2.dll
  • %Application Data%\AppCache\1\cygnghttp2-14.dll
  • %Application Data%\AppCache\1\cygpsl-5.dll
  • %Application Data%\AppCache\1\cygsasl2-3.dll
  • %Application Data%\AppCache\1\cygssh2-1.dll
  • %Application Data%\AppCache\1\cygssl-1.0.0.dll
  • %Application Data%\AppCache\1\cygunistring-2.dll
  • %Application Data%\AppCache\1\cygwin1.dll
  • %Application Data%\AppCache\1\cygz.dll

(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 and executes the following files:

  • %Application Data%\AppCache\1\java.exe←detected by Trend Micro as TROJ_COINMINER.AUSF

(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 adds the following processes:

  • "%System%\schtasks.exe" /Delete /TN "UpdateService" /F
  • "%System%\schtasks.exe" /Create /RU SYSTEM /SC ONSTART /TN "UpdateService" /TR "\"%All Users Profile%\UpdateService\UpdateService.exe\" -t"
  • "%System%\schtasks.exe" /Run /TN "UpdateService"
  • "%System%\schtasks.exe" /Delete /TN "UpdateService" /F
  • "%System%\schtasks.exe" /Create /RU SYSTEM /SC ONSTART /TN "UpdateService" /TR "\"%All Users Profile%\UpdateService\UpdateService.exe\" -t"

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.. %All Users Profile% is the All Users folder, where it usually is C:\Documents and Settings\All Users on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\ProgramData 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 uses Windows Task Scheduler to create a scheduled task that executes the dropped copy.

It creates the following folders:

  • %Application Data%\AppCache\1

(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.)

Autostart Technique

The scheduled task executes the malware every:

  • Windows Startup

Dropping Routine

This Trojan drops the following files:

  • %Windows%\Tasks\UpdateService.job

(Note: %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

Other Details

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

  • http://{BLOCKED}op.ru/templates/beez3/html/layouts/joomla/system/log.php?url=/update/check
  • {BLOCKED}op.ru
  • {BLOCKED}eb.com
  • xmr7.{BLOCKED}-pool.fr:3333

  SOLUTION

Minimum Scan Engine: 9.850

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

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.  
  • %Application Data%\AppCache\1

Step 4

Search and delete this file

[ 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.
  • %Windows%\Tasks\UpdateService.job

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_COINMINER.WINQ. 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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