Analysis by: Kathleen Notario
 PLATFORM:

Windows 98, ME, NT, 2000, XP, Server 2003

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Trend Micro has received multiple samples of this malware from a malicious domain source that have infected many clients. These indicate that this malware poses a high risk to users due to the increased possibility of infection.

To get a one-glance comprehensive view of the behavior of this Trojan, refer to the Threat Diagram shown below.

This Trojan may be downloaded unknowingly by a user when visiting malicious website(s). However, as of this writing, the said sites are inaccessible.

  TECHNICAL DETAILS

File Size: 61,952 bytes
File Type: PE
Memory Resident: Yes
Initial Samples Received Date: 05 Jul 2010
Payload: Downloads files

Arrival Details

This Trojan may be downloaded unknowingly by a user when visiting the following malicious website(s):

  • http://{BLOCKED}bi.in

However, as of this writing, the said sites are inaccessible.

Installation

This Trojan drops the following files:

  • %Windows%\{random file name}.dll - also detected as TROJ_HILOTI.AID

(Note: %Windows% is the Windows folder, which is usually C:\Windows or C:\WINNT.)

It adds the following mutexes to ensure that only one of its copies runs at any one time:

  • 930b413c

It injects threads into the following normal process(es):

  • EXPLORER.EXE

Autostart Technique

This Trojan creates the following registry entries to enable automatic execution of dropped component at every system startup:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Run
{random} = rundll32.exe %Windows%\{random file name}.dll,Startup

Download Routine

This Trojan accesses the following websites to download files:

  • rc2.{BLOCKED}loading.com
  • http://{BLOCKED}da0702.agulhal.com/get2.php
  • http://{BLOCKED}da0703.agulhal.com/get2.php
  • http://{BLOCKED}da0703.gerborn.com/get2.php

  SOLUTION

Minimum Scan Engine: 8.900
FIRST VSAPI PATTERN FILE: 7.286.06
FIRST VSAPI PATTERN DATE: 05 Jul 2010
VSAPI OPR PATTERN File: 7.291.00
VSAPI OPR PATTERN Date: 06 Jul 2010

Step 1

For Windows XP and Windows Server 2003 users, before doing any scans, please make sure you disable System Restore to allow full scanning of your computer.

Step 2

Restart in Safe Mode

[ Learn More ]

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\Microsoft\Windows\CurrentVersion\Run
    • {random} = rundll32.exe %Windows%\{random file name}.dll,Startup

Step 4

Restart in normal mode and scan your computer with your Trend Micro product for files detected as TROJ_HILOTI.AID. 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.