TROJ_DLOADER.UOU

October 08, 2012
 Analysis by: Cris Nowell Pantanilla
 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

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

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

  TECHNICAL DETAILS

File Size:

230,912 bytes

File Type:

PE

Memory Resident:

Yes

Initial Samples Received Date:

17 Apr 2008

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.

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

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\ndp
Uns_Code = {values}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\InfoDelivery\
Restrictions
NoSearchBox = 0

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Enable Browser Extensions = yes

Download Routine

This Trojan accesses the following websites to download files:

  • http://www.dpoint.co.kr/toolbarinfo/uninstall.php

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

  SOLUTION

Minimum Scan Engine:

8.900

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

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
    • ndp
  • In HKEY_CLASSES_ROOT\CLSID
    • {F2CF5485-4E02-4f68-819C-B92DE9277049}

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\Internet Explorer\Main
    • Enable Browser Extensions=yes
  • In HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\InfoDelivery\Restrictions
    • NoSearchBox=0'

Step 4

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