TROJ_AGENT.HTOM

October 12, 2012
 ALIASES:

Generic PUP.x. (McAfee); HackTool.Win32.Agent.hq (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.1643536 (FSecure)

 PLATFORM:

Windows 2000, Windows XP, Windows Server 2003

 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:

167,867 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

02 May 2012

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 creates the following folders:

  • %User Temp%\is-U4UD8.tmp
  • %Program Files%\Cracklock
  • %Program Files%\Cracklock\Bin
  • %Program Files%\Cracklock\Languages
  • %Program Files%\Cracklock\Examples
  • %Program Files%\Cracklock\Help
  • %Program Files%\Cracklock\Help\clressp.dll
  • %Program Files%\Cracklock\Help\clressp.dll\html
  • %Program Files%\Cracklock\Help\clressp.dll\images
  • %Program Files%\Cracklock\Help\clresus.dll
  • %Program Files%\Cracklock\Help\clresus.dll\html
  • %Program Files%\Cracklock\Help\clresus.dll\images
  • %Program Files%\Cracklock\Help\clresfr.dll
  • %Program Files%\Cracklock\Help\clresfr.dll\images
  • %Program Files%\Cracklock\Help\clresfr.dll\html
  • %Program Files%\Cracklock\Help\commun
  • %Program Files%\Cracklock\Help\commun\images

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.. %Program Files% is the default Program Files folder, usually C:\Program Files.)

Other System Modifications

This Trojan adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MicroBest Cracklock 3.8.1_is1

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MicroBest Cracklock 3.8.1_is1
DisplayName = "MicroBest Cracklock 3.8.1"

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Uninstall\
MicroBest Cracklock 3.8.1_is1
UninstallString = "%Program Files%\Cracklock\unins000.exe"

Dropping Routine

This Trojan drops the following files:

  • %User Temp%\INS1.tmp
  • %Program Files%\Cracklock\unins000.msg

(Note: %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000, XP, and Server 2003.. %Program Files% is the default Program Files folder, usually C:\Program Files.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine:

9.200

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
    • MicroBest Cracklock 3.8.1_is1

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_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\MicroBest Cracklock 3.8.1_is1
    • DisplayName = "MicroBest Cracklock 3.8.1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\MicroBest Cracklock 3.8.1_is1
    • UninstallString = "%Program Files%\Cracklock\unins000.exe"

Step 4

Search and delete these files

[ Learn More ]
There may be some component 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.
  • %User Temp%\INS1.tmp
  • %Program Files%\Cracklock\unins000.msg

Step 5

Search and delete these folders

[ Learn More ]
Please make sure you check the Search Hidden Files and Folders checkbox in the More advanced options option to include all hidden folders in the search result.
  • %User Temp%\is-U4UD8.tmp
  • %Program Files%\Cracklock
  • %Program Files%\Cracklock\Bin
  • %Program Files%\Cracklock\Languages
  • %Program Files%\Cracklock\Examples
  • %Program Files%\Cracklock\Help
  • %Program Files%\Cracklock\Help\clressp.dll
  • %Program Files%\Cracklock\Help\clressp.dll\html
  • %Program Files%\Cracklock\Help\clressp.dll\images
  • %Program Files%\Cracklock\Help\clresus.dll
  • %Program Files%\Cracklock\Help\clresus.dll\html
  • %Program Files%\Cracklock\Help\clresus.dll\images
  • %Program Files%\Cracklock\Help\clresfr.dll
  • %Program Files%\Cracklock\Help\clresfr.dll\images
  • %Program Files%\Cracklock\Help\clresfr.dll\html
  • %Program Files%\Cracklock\Help\commun
  • %Program Files%\Cracklock\Help\commun\images

Step 6

Scan your computer with your Trend Micro product to delete files detected as TROJ_AGENT.HTOM. 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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