Analysis by: Anthony Joe Melgarejo
ALIASES:

VirTool:Win32/Injector.gen!DP (Microsoft), W32/Jorik.CTPG!tr (Fortinet), a variant of Win32/Injector.AGNL trojan (ESET)

 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:

  • 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 executes then deletes itself afterward.

  TECHNICAL DETAILS

File Size: 115,553 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 14 May 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.

Installation

This Trojan drops and executes the following files:

  • %User Temp%\{random numbers 3}.bat - deleted afterwards

(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.

Download Routine

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

  • http://{BLOCKED}ilzabrze.pl/tmp/sm.exe
  • http://{BLOCKED}ilzabrze.pl/tmp/np.exe

It saves the files it downloads using the following names:

  • %User Temp%\{random numbers 1}.exe
  • %User Temp%\{random numbers 2}.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.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • http://{BLOCKED}aveltalk.com/ceqhsem.php

NOTES:
%User Temp%\{random numbers 3}.BAT is used to delete the downloaded file %User Temp%\{random numbers 1}.EXE.

  SOLUTION

Minimum Scan Engine: 9.300
FIRST VSAPI PATTERN FILE: 9.918.05
FIRST VSAPI PATTERN DATE: 14 May 2013
VSAPI OPR PATTERN File: 9.919.00
VSAPI OPR PATTERN Date: 15 May 2013

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 files

[ Learn More ]
There may be some component 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 numbers 1}.exe
  • %User Temp%\{random numbers 2}.exe

Step 3

Scan your computer with your Trend Micro product to delete files detected as TROJ_DLOADR.BPF. 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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