ALIASES:

DDoS:Win32/Nitol.B (Microsoft); Downloader (Symantec); HEUR:Trojan.Win32.Generic (Kaspersky); Troj/Nitol-R (Sophos); Trojan.Win32.Scar.aa (v) (Sunbelt); Trojan horse PSW.OnlineGames4.BBOB (AVG)

 PLATFORM:

Windows

 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.

  TECHNICAL DETAILS

File Size: 61,440 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 21 Oct 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:

  • %System%\hutpug.exe

(Note: %System% is the Windows system folder, where it usually is C:\Windows\System32 on all Windows operating system versions.)

Other System Modifications

This Trojan adds the following registry entries:

HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\
Services\aspnet_states
Description = "Provides support for out-of-to-process"

Dropping Routine

This Trojan drops the following files:

  • gei33.dll
  • %User Profile%\{AC76BA86-7AD7-1033-7B44-AA0000000001}\lpk.dll
  • %Program Files%\Adobe\Reader 10.0\Reader\lpk.dll
  • %Program Files%\Common Files\Adobe\ARM\1.0\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\DW\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\MSInfo\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\Speech\lpk.dll
  • %Program Files%\Internet Explorer\Connection Wizard\lpk.dll
  • %Program Files%\Internet Explorer\lpk.dll
  • %Program Files%\Messenger\lpk.dll
  • %Program Files%\Movie Maker\lpk.dll
  • %Program Files%\MSN\MSNCoreFiles\Install\MSN9Components\lpk.dll
  • %Program Files%\MSN\MSNCoreFiles\Install\lpk.dll
  • %Program Files%\MSN Gaming Zone\Windows\lpk.dll
  • %Program Files%\NetMeeting\lpk.dll
  • %Program Files%\Outlook Express\lpk.dll
  • %Program Files%\Windows Media Player\lpk.dll
  • %Program Files%\Windows NT\Accessories\lpk.dll
  • %Program Files%\Windows NT\lpk.dll
  • %Program Files%\Windows NT\Pinball\lpk.dll
  • %Program Files%\WinPcap\lpk.dll
  • %Windows%\$MSI31Uninstall_KB893803v2$\lpk.dll
  • %Windows%\$MSI31Uninstall_KB893803v2$\spuninst\lpk.dll
  • %Windows%\$NtUninstallWIC$\spuninst\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\ComSvcConfig\bb3c2f59a821abc54f420f3a9e051d6a\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\dfsvc\837fe02bdcf637d5bf1e5ffb935ebb80\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\MSBuild\aa99ebdd26e5d493fec18b1714458782\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\PresentationFontCac#\4ce7fd62d4107fbe996ab305eb21ee6a\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\ServiceModelReg\feac66e81309d67b48f7a9f4cb98f7c8\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\SMSvcHost\a098c66aa40d958878f3f5344e6ae1a4\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\WsatConfig\13f498f606b7cb97c086eea149b8c872\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\ComSvcConfig\51819c709096229ee187a7feee395d9f\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\dfsvc\b9b6069e6da06eb57e89cc544397f735\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\Microsoft.Workflow.#\6a8da5dd61b1fcfed27f84047a3e2bad\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\MSBuild\aa25092606e5e9826db7a7bd0adb9b2b\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\SMSvcHost\38f0d77629891e7808424103aaef0728\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\WsatConfig\3c0d21e75c9a48aba6fba3ddff0fcf39\lpk.dll
  • %Windows%\lpk.dll
  • %Windows%\Help\Tours\mmTour\lpk.dll

(Note: %User Profile% is a user's profile folder, where it usually is C:\Documents and Settings\{user name} on Windows 2000, Windows Server 2003, and Windows XP (32- and 64-bit); C:\Users\{user name} on Windows Vista (32- and 64-bit), Windows 7 (32- and 64-bit), Windows 8 (32- and 64-bit), Windows 8.1 (32- and 64-bit), Windows Server 2008, and Windows Server 2012.. %Program Files% is the Program Files folder, where it usually is C:\Program Files on all Windows operating system versions; C:\Program Files (x86) for 32-bit applications running on Windows 64-bit operating systems.. %Windows% is the Windows folder, where it usually is C:\Windows on all Windows operating system versions.)

Other Details

This Trojan connects to the following possibly malicious URL:

  • {BLOCKED}0

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

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\aspnet_states
    • Description = "Provides support for out-of-to-process"

Step 3

Search and delete these components

[ Learn More ]
There may be some components 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.
  • gei33.dll
  • %User Profile%\{AC76BA86-7AD7-1033-7B44-AA0000000001}\lpk.dll
  • %Program Files%\Adobe\Reader 10.0\Reader\lpk.dll
  • %Program Files%\Common Files\Adobe\ARM\1.0\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\DW\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\MSInfo\lpk.dll
  • %Program Files%\Common Files\Microsoft Shared\Speech\lpk.dll
  • %Program Files%\Internet Explorer\Connection Wizard\lpk.dll
  • %Program Files%\Internet Explorer\lpk.dll
  • %Program Files%\Messenger\lpk.dll
  • %Program Files%\Movie Maker\lpk.dll
  • %Program Files%\MSN\MSNCoreFiles\Install\MSN9Components\lpk.dll
  • %Program Files%\MSN\MSNCoreFiles\Install\lpk.dll
  • %Program Files%\MSN Gaming Zone\Windows\lpk.dll
  • %Program Files%\NetMeeting\lpk.dll
  • %Program Files%\Outlook Express\lpk.dll
  • %Program Files%\Windows Media Player\lpk.dll
  • %Program Files%\Windows NT\Accessories\lpk.dll
  • %Program Files%\Windows NT\lpk.dll
  • %Program Files%\Windows NT\Pinball\lpk.dll
  • %Program Files%\WinPcap\lpk.dll
  • %Windows%\$MSI31Uninstall_KB893803v2$\lpk.dll
  • %Windows%\$MSI31Uninstall_KB893803v2$\spuninst\lpk.dll
  • %Windows%\$NtUninstallWIC$\spuninst\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\ComSvcConfig\bb3c2f59a821abc54f420f3a9e051d6a\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\dfsvc\837fe02bdcf637d5bf1e5ffb935ebb80\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\MSBuild\aa99ebdd26e5d493fec18b1714458782\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\PresentationFontCac#\4ce7fd62d4107fbe996ab305eb21ee6a\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\ServiceModelReg\feac66e81309d67b48f7a9f4cb98f7c8\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\SMSvcHost\a098c66aa40d958878f3f5344e6ae1a4\lpk.dll
  • %Windows%\assembly\NativeImages_v2.0.50727_32\WsatConfig\13f498f606b7cb97c086eea149b8c872\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\ComSvcConfig\51819c709096229ee187a7feee395d9f\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\dfsvc\b9b6069e6da06eb57e89cc544397f735\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\Microsoft.Workflow.#\6a8da5dd61b1fcfed27f84047a3e2bad\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\MSBuild\aa25092606e5e9826db7a7bd0adb9b2b\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\SMSvcHost\38f0d77629891e7808424103aaef0728\lpk.dll
  • %Windows%\assembly\NativeImages_v4.0.30319_32\WsatConfig\3c0d21e75c9a48aba6fba3ddff0fcf39\lpk.dll
  • %Windows%\lpk.dll
  • %Windows%\Help\Tours\mmTour\lpk.dll

Step 4

Scan your computer with your Trend Micro product to delete files detected as TROJ_NITOL.DUKKX. 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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