TROJ_DLOADER.FUD

 Analysis by: Rika Joi Gregorio

 ALIASES:

Trojan-Downloader.Banload(Ikarus), a variant of Win32/TrojanDownloader.VB.QDN trojan(Eset), LooksLike.Win32.Malware!vb (v)(Sunbelt)

 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: 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 does not have any propagation routine.

It does not have any backdoor routine.

It does not drop any other file.

It does not have any information-stealing capability.

  TECHNICAL DETAILS

File Size:

14,848 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

07 Jun 2013

Payload:

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.

Other System Modifications

This Trojan adds the following registry keys:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Ext

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Ext\CLSID

HKEY_LOCAL_MACHINE\SOFTWARE\Description

HKEY_LOCAL_MACHINE\SOFTWARE\Description\
Microsoft

HKEY_LOCAL_MACHINE\SOFTWARE\Description\
Microsoft\Rpc

HKEY_LOCAL_MACHINE\SOFTWARE\Description\
Microsoft\Rpc\UuidTemporaryData

It adds the following registry entries:

HKEY_CURRENT_USER\AppEvents\Schemes\
Apps\Explorer\Navigating
.Default = ""

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Ext\CLSID
(Default) = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Description\
Microsoft\Rpc\UuidTemporaryData
NetworkAddress = "{random}"

HKEY_LOCAL_MACHINE\SOFTWARE\Description\
Microsoft\Rpc\UuidTemporaryData
NetworkAddressLocal = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Browser Helper Objects
NoExplorer = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Ext\
PreApproved
(Default) = ""

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\policies\
system
EnableLUA = "0"

Propagation

This Trojan does not have any propagation routine.

Backdoor Routine

This Trojan does not have any backdoor routine.

Dropping Routine

This Trojan does not drop any other file.

Download Routine

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

  • {BLOCKED}ti.{BLOCKED}fcssdo.us-east-1.rds.amazonaws.com

It saves the files it downloads using the following names:

  • %System%\md2ahhm.dll - detected as TROJ_GENTA.FUD

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.)

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:

9.300

FIRST VSAPI PATTERN FILE:

9.966.02

FIRST VSAPI PATTERN DATE:

07 Jun 2013

VSAPI OPR PATTERN File:

9.967.00

VSAPI OPR PATTERN Date:

08 Jun 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

Remove malware/grayware files dropped/downloaded by TROJ_DLOADER.FUD

  • TROJ_GENTA.FUD

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\Microsoft\Windows\CurrentVersion\Policies
    • Ext
  • In HKEY_LOCAL_MACHINE\SOFTWARE
    • Description

Step 4

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\AppEvents\Schemes\Apps\Explorer\Navigating
    • .Default = ""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects
    • NoExplorer = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Ext\PreApproved
    • (Default) = ""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\policies\system
    • EnableLUA = "0"

Step 5

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