TROJ_DROPPER.XXTT


 ALIASES:

Trojan.Win32.Fusing.cf (v) (Sunbelt); Trojan horse Agent4.BYWF (AVG)

 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 deletes itself after execution.

  TECHNICAL DETAILS

File Size:

16,815,616 bytes

File Type:

EXE

Memory Resident:

Yes

Initial Samples Received Date:

18 Aug 2014

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:

  • %Program Files%\Windows NT\Equckka.exe

(Note: %Program Files% is the default Program Files folder, usually C:\Program Files in Windows 2000, Server 2003, and XP (32-bit), Vista (32-bit), and 7 (32-bit), or C:\Program Files (x86) in Windows XP (64-bit), Vista (64-bit), and 7 (64-bit).)

Autostart Technique

This Trojan 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\Wsrsht drgswqyo

Other System Modifications

This Trojan adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wsrsht drgswqyo
ConnectGroup = "ĬÈÏ·Ö×é"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wsrsht drgswqyo
MarkTime = "2014-07-29 17:26"

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\Wsrsht drgswqyo
Description = "Moggoy mucmckeicmgcyyogiy"

Dropping Routine

This Trojan drops the following files:

  • %System Root%\5900.vbs

(Note: %System Root% is the root folder, which is usually C:\. It is also where the operating system is located.)

Other Details

This Trojan deletes itself after execution.

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.700

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

Restart in Safe Mode

[ Learn More ]

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_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
    • Wsrsht drgswqyo

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_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wsrsht drgswqyo
    • ConnectGroup = "ĬÈÏ·Ö×é"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wsrsht drgswqyo
    • MarkTime = "2014-07-29 17:26"
  • In HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Wsrsht drgswqyo
    • Description = "Moggoy mucmckeicmgcyyogiy"

Step 5

Search and delete this file

[ Learn More ]
There may be some 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.
  • %System Root%\5900.vbs

Step 6

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