arrow_back
search
close

TROJ_ISTAZV.NIL

September 07, 2013
 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.

  TECHNICAL DETAILS

File Size:

95,680 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

07 Sep 2013

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 adds the following registry keys:

HKEY_CURRENT_USER\Software\Dwnloader.net

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Dwnloader.net
GUID = "5A02645A-938C-4831-8744-A3740545A649"

HKEY_CURRENT_USER\Software\Dwnloader.net
installDate = "13017111679307"

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\init.xml
  • %User Temp%\hd.vbs
  • %User Temp%\zon7.tmp
  • %User Temp%\zon9.tmp
  • %User Temp%\zonD.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 connects to the following possibly malicious URL:

  • http://stat.{BLOCKED}u.com/installer.html?{random characters}
  • http://dl.{BLOCKED}v.net/{random path}?ub39=true

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

Delete this registry key

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software
    • Dwnloader.net

Step 3

Delete this registry value

[ Learn More ]

Important: Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this step only if you know how or you can ask assistance from your system administrator. Else, check this Microsoft article first before modifying your computer's registry.

  • In HKEY_CURRENT_USER\Software\Dwnloader.net
    • GUID = "5A02645A-938C-4831-8744-A3740545A649"
  • In HKEY_CURRENT_USER\Software\Dwnloader.net
    • installDate = "13017111679307"

Step 4

Search and delete these components

[ Learn More ]
There may be some components 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%\init.xml
  • %User Temp%\hd.vbs
  • %User Temp%\zon7.tmp
  • %User Temp%\zon9.tmp
  • %User Temp%\zonD.tmp

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_ISTAZV.NIL. 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.