TROJ_AGENT.YMNJW

 Analysis by: Cris Nowell Pantanilla

 ALIASES:

Win32.Trojan.Agent.7YAO9A (GData)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted:

  • In the wild: Yes

  OVERVIEW


This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites. It may be manually installed by a user.

  TECHNICAL DETAILS

File Size:

1,898,496 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

29 Sep 2016

Arrival Details

This Trojan arrives on a system as a file dropped by other malware or as a file downloaded unknowingly by users when visiting malicious sites.

It may be manually installed by a user.

Installation

This Trojan drops the following files:

  • %User Temp%\TempFolder.aaa\Macromedia.lok
  • %User Temp%\TempFolder.aaa\xtras\Animated GIF Asset.x32
  • %User Temp%\TempFolder.aaa\xtras\DirectSound.x32
  • %User Temp%\TempFolder.aaa\xtras\Flash Asset.x32
  • %User Temp%\TempFolder.aaa\xtras\Font Xtra.x32
  • %User Temp%\TempFolder.aaa\xtras\INetURL.x32
  • %User Temp%\TempFolder.aaa\xtras\MacroMix.x32
  • %User Temp%\TempFolder.aaa\xtras\NetFile.x32
  • %User Temp%\TempFolder.aaa\xtras\NetLingo.x32
  • %User Temp%\TempFolder.aaa\xtras\QT6Asset.x32
  • %User Temp%\TempFolder.aaa\xtras\Sound Control.x32
  • %User Temp%\TempFolder.aaa\xtras\SWADCmpr.x32
  • %User Temp%\TempFolder.aaa\xtras\Text Asset.x32
  • %User Temp%\TempFolder.aaa\xtras\TextXtra.x32

(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.)

It creates the following folders:

  • %User Temp%\TempFolder.aaa
  • %User Temp%\TempFolder.aaa\xtras

(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.)

NOTES:

It requires a certain version of Adobe Shockwave to execute properly.

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

12.806.05

FIRST VSAPI PATTERN DATE:

29 Sep 2016

VSAPI OPR PATTERN File:

12.807.00

VSAPI OPR PATTERN Date:

30 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

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.  %User Temp%\TempFolder.aaa

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_AGENT.YMNJW. 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.


Did this description help? Tell us how we did.