TROJ_DROPPER.ZYG

February 21, 2014
 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 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 deletes itself after execution.

  TECHNICAL DETAILS

File Size:

154,112 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

21 Feb 2014

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.

Other System Modifications

This Trojan deletes the following files:

  • %User Temp%\58e0ef.mst
  • %User Temp%\AdobeARM.log
  • %User Temp%\AdobeSFX.log
  • %User Temp%\ASPNETSetup_00000.log
  • %User Temp%\ASPNETSetup_00001.log
  • %User Temp%\ASPNETSetup_00002.log
  • %User Temp%\dd_depcheck_NETFX_EXP_35.txt
  • %User Temp%\dd_dotnetfx35error.txt
  • %User Temp%\dd_dotnetfx35install.txt
  • %User Temp%\dd_dotNetFx40_Full_x86_x64_decompression_log.txt
  • %User Temp%\dd_MSXML6_MSI0686.txt
  • %User Temp%\dd_netfx20MSI7F16.txt
  • %User Temp%\dd_netfx20UI7F16.txt
  • %User Temp%\dd_NET_Framework20_Setup06A7.txt
  • %User Temp%\dd_NET_Framework30_Setup0775.txt
  • %User Temp%\dd_NET_Framework35_MSI07B9.txt
  • %User Temp%\dd_RGB9RAST_x86.msi0683.txt
  • %User Temp%\dd_vcredistMSI3CAA.txt
  • %User Temp%\dd_vcredistMSI7C21.txt
  • %User Temp%\dd_vcredistUI3CAA.txt
  • %User Temp%\dd_vcredistUI7C21.txt
  • %User Temp%\dd_wcf_CA_smci_20111017_044900_062.txt
  • %User Temp%\dd_wcf_retCA29BA.txt
  • %User Temp%\dd_WIC.txt
  • %User Temp%\dd_XPS.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Core_x86.msi.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Extended_x86.msi.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578.html
  • %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642-MSI_vc_red.msi.txt
  • %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642.html
  • %User Temp%\uxeventlog.txt
  • %User Temp%\vminst.log_20111016_212239_Failed.log
  • %User Temp%\vminst.log_20130313_012028.log
  • %User Temp%\vminst.log_20130313_012352_Failed.log
  • %User Temp%\vmmsi.log_20111016_212246_Failed.log
  • %User Temp%\vmmsi.log_20130313_012028.log
  • %User Temp%\vmmsi.log_20130313_012352_Failed.log
  • %User Temp%\WSFF8.tmp
  • %User Temp%\WSFF9.tmp
  • %User Temp%\tmp3.tmp

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Other Details

This Trojan deletes itself after execution.

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.300

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

Scan your computer with your Trend Micro product to delete files detected as TROJ_DROPPER.ZYG. 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.

Step 3

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %User Temp%\58e0ef.mst
  • %User Temp%\AdobeARM.log
  • %User Temp%\AdobeSFX.log
  • %User Temp%\ASPNETSetup_00000.log
  • %User Temp%\ASPNETSetup_00001.log
  • %User Temp%\ASPNETSetup_00002.log
  • %User Temp%\dd_depcheck_NETFX_EXP_35.txt
  • %User Temp%\dd_dotnetfx35error.txt
  • %User Temp%\dd_dotnetfx35install.txt
  • %User Temp%\dd_dotNetFx40_Full_x86_x64_decompression_log.txt
  • %User Temp%\dd_MSXML6_MSI0686.txt
  • %User Temp%\dd_netfx20MSI7F16.txt
  • %User Temp%\dd_netfx20UI7F16.txt
  • %User Temp%\dd_NET_Framework20_Setup06A7.txt
  • %User Temp%\dd_NET_Framework30_Setup0775.txt
  • %User Temp%\dd_NET_Framework35_MSI07B9.txt
  • %User Temp%\dd_RGB9RAST_x86.msi0683.txt
  • %User Temp%\dd_vcredistMSI3CAA.txt
  • %User Temp%\dd_vcredistMSI7C21.txt
  • %User Temp%\dd_vcredistUI3CAA.txt
  • %User Temp%\dd_vcredistUI7C21.txt
  • %User Temp%\dd_wcf_CA_smci_20111017_044900_062.txt
  • %User Temp%\dd_wcf_retCA29BA.txt
  • %User Temp%\dd_WIC.txt
  • %User Temp%\dd_XPS.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Core_x86.msi.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578-MSI_netfx_Extended_x86.msi.txt
  • %User Temp%\Microsoft .NET Framework 4 Setup_20111016_234618578.html
  • %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642-MSI_vc_red.msi.txt
  • %User Temp%\Microsoft Visual C++ 2010 x86 Redistributable Setup_20111020_000954642.html
  • %User Temp%\uxeventlog.txt
  • %User Temp%\vminst.log_20111016_212239_Failed.log
  • %User Temp%\vminst.log_20130313_012028.log
  • %User Temp%\vminst.log_20130313_012352_Failed.log
  • %User Temp%\vmmsi.log_20111016_212246_Failed.log
  • %User Temp%\vmmsi.log_20130313_012028.log
  • %User Temp%\vmmsi.log_20130313_012352_Failed.log
  • %User Temp%\WSFF8.tmp
  • %User Temp%\WSFF9.tmp
  • %User Temp%\tmp3.tmp


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