Analysis by: Jaime Benigno Reyes

ALIASES:

Trojan-Spy.Win32.Zbot.sjwc (Kaspersky)

 PLATFORM:

Windows 2000, Windows Server 2003, Windows XP (32-bit, 64-bit), Windows Vista (32-bit, 64-bit), Windows 7 (32-bit, 64-bit)

 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, Dropped by other malware

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 executes then deletes itself afterward.

It does not have any propagation routine.

It does not have any backdoor routine.

It executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system. As of this writing, the said sites are inaccessible.

It does not have any information-stealing capability.

  TECHNICAL DETAILS

File Size: 141,836 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 16 May 2014
Payload: Connects to URLs/IPs, Downloads files

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.

Installation

This Trojan drops the following component file(s):

  • %User Temp%\{random}.bat - used for deleting itself

(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.)

It executes then deletes itself afterward.

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications

HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
ImageView

HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
ImageView\Recent File List

HKEY_CURRENT_USER\Software\Local AppWizard-Generated Applications\
ImageView\Settings

HKEY_CURRENT_USER\Software\{10 random letters}

HKEY_LOCAL_MACHINE\SOFTWARE\{10 random letters}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\{10 random letters}
License = "1480"

HKEY_LOCAL_MACHINE\SOFTWARE\{10 random letters}
License = "1480"

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Download Routine

This Trojan connects to the following website(s) to download and execute a malicious file:

  • http://{BLOCKED}-leaf.com/com_phocaguestbook/ajax
  • http://{BLOCKED}-leaf.com/com_phocaguestbook/jquery
  • http://{BLOCKED}-gimbl.com/b/shoe

It saves the files it downloads using the following names:

  • %User Temp%\{random}.tmp
  • %User Temp%\UpdateFlashPlayer_{random}.exe

(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.)

It then executes the downloaded files. As a result, malicious routines of the downloaded files are exhibited on the affected system.

As of this writing, the said sites are inaccessible.

Information Theft

This Trojan does not have any information-stealing capability.

NOTES:

It does not have rootkit capabilities.

It does not exploit any vulnerability.

  SOLUTION

Minimum Scan Engine: 9.700
FIRST VSAPI PATTERN FILE: 10.798.04
FIRST VSAPI PATTERN DATE: 16 May 2014
VSAPI OPR PATTERN File: 10.799.00
VSAPI OPR PATTERN Date: 17 May 2014

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

Identify and terminate files detected as TROJ_DLOADER.OPS

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 3

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
    • Local AppWizard-Generated Applications
  • In HKEY_CURRENT_USER\Software
    • {10 random letters}
  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • {10 random letters}

Step 4

Search and delete these files

[ 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.
  • %User Temp%\{random}.tmp
  • %User Temp%\UpdateFlashPlayer_{random}.exe
  • %User Temp%\{random}.bat

Step 5

Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOADER.OPS. 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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