Analysis by: Sabrina Lei Sioting
 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

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 the files it drops, prompting the affected system to exhibit the malicious routines they contain.

It connects to certain websites to send and receive information.

  TECHNICAL DETAILS

File Size: 51,712 bytes
File Type: EXE
Memory Resident: Yes
Initial Samples Received Date: 21 Jul 2009

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 copies of itself into the affected system:

  • %System%\svchost.exe:exe.exe

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

Autostart Technique

This Trojan registers itself as a system service to ensure its automatic execution at every system startup by adding the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
Type = "110"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
Start = "2"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
ErrorControl = "1"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
ImagePath = "%System%\svchost.exe:exe.exe"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
DisplayName = "ICF"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
Group = "TDI"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF
ObjectName = "LocalSystem"

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF\Security
Security = "{hex values}"

It registers as a system service to ensure its automatic execution at every system startup by adding the following registry keys:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF\Security

Other System Modifications

This Trojan adds the following registry keys as part of its installation routine:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\ICF\Security

Dropping Routine

This Trojan executes the files it drops, prompting the affected system to exhibit the malicious routines they contain.

Other Details

This Trojan connects to the following website to send and receive information:

  • {BLOCKED}.info
  • {BLOCKED}.info
  • {BLOCKED}zorada.biz
  • {BLOCKED}anora.com
  • {BLOCKED}.0rg

  SOLUTION

Minimum Scan Engine: 9.300

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

Scan your computer with your Trend Micro product and note files detected as TROJ_MEGAD.B

Step 3

Restart in Safe Mode

[ Learn More ]

Step 4

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. Before you could do this, you must restart in Safe Mode. For instructions on how to do this, you may refer to this page If the preceding step requires you to restart in safe mode, you may proceed to edit the system registry.

 
  • In HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • ICF

Step 5

To delete ADS files:

  1. Download Streams.exe from this Microsoft page.
  2. Extract the contents of this file to a location of your choice.
  3. Open a command prompt window. To do this:
    • On Windows 2000, XP, and Server 2003:
      Click Start>Run. In the input box, type CMD, and press Enter.
    • On Windows Vista and 7:
      Click the Windows button, type CMD in the search box, and press Enter.
  4. In the command prompt, type the following, then press Enter:
    CD {Path where contents of downloaded file was extracted}
  5. Still in the command prompt type the following then press Enter:
    Streams.exe -d %System%
  6. Type exit then press Enter.

Step 6

Scan your computer with your Trend Micro product to delete files detected as TROJ_MEGAD.B. 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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