ALIASES:

Trojan:Win32/Startpage.LM (Microsoft); Generic StartPage!bcr (McAfee); Trojan.Startpage (Symantec); Trojan.Win32.StartPage.adpp, Trojan.Win32.StartPage.adpp (Kaspersky); Trojan.Win32.Generic.pak!cobra (Sunbelt); Trojan.Generic.KD.27898 (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.

It disables Task Manager, Registry Editor, and Folder Options.

  TECHNICAL DETAILS

File Size: 79,872 bytes
File Type: EXE
Memory Resident: No
Initial Samples Received Date: 03 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 drops the following copies of itself into the affected system:

  • %User Temp%\Del1.tmp

(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, or C:\Users\{user name}\AppData\Local\Temp on Windows Vista and 7.)

Other System Modifications

This Trojan modifies the following file(s):

  • %Start Menu%\Programs\Internet Explorer.lnk

(Note: %Start Menu% is the current user's Start Menu folder, which is usually C:\Windows\Start Menu or C:\Documents and Settings\{User name}\Start Menu on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\AppData\Roaming\Microsoft\Windows\Start Menu on Windows Vista and 7.)

It adds the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\
NoAddOns

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\
NoAddOns\Command

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell\
NoAddOns

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell\
NoAddOns\Command

It adds the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\
NoAddOns
MUIVerb = "@shdoclc.dll,-10241"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}
InfoTip = "????????"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell\
NoAddOns
MUIVerb = "@shdoclc.dll,-10241"

It modifies the following registry entries:

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}
InfoTip = "@shdoclc.dll,-881"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}
LocalizedString = "@shdoclc.dll,-880"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\InProcServer32
ThreadingModel = "Apartment"

(Note: The default value data of the said registry entry is Apartment.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
Attributes = "0"

(Note: The default value data of the said registry entry is 24.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}
LocalizedString = "????"

(Note: The default value data of the said registry entry is {random values}.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\InProcServer32
ThreadingModel = "Apartment"

(Note: The default value data of the said registry entry is Apartment.)

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\ShellFolder
Attributes = "0"

(Note: The default value data of the said registry entry is 20180000.)

It creates the following registry entry(ies) to disable Task Manager, Registry Tools and Folder Options:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
Explorer
NoInternetIcon = "1"

Dropping Routine

This Trojan drops the following files:

  • %User Profile%\Quick Launch\Launch Internet Explorer Browser.lnk
  • %Desktop%\Internet Explorer.lnk

(Note: %User Profile% is the current user's profile folder, which is usually C:\Documents and Settings\{user name} on Windows 2000, XP, and Server 2003, or C:\Users\{user name} on Windows Vista and 7.. %Desktop% is the current user's desktop, which is usually C:\Documents and Settings\{User Name}\Desktop on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\Desktop on Windows Vista and 7.)

This report is generated via an automated analysis system.

  SOLUTION

Minimum Scan Engine: 9.200

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

Enable Registry Editor, Task Manager, and Folder options

[ Learn More ]
By doing this step, you also enable other applications/programs disabled by this malware/grayware/spyware.

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\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell
    • NoAddOns
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\NoAddOns
    • Command
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}
    • shell
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell
    • NoAddOns
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell\NoAddOns
    • Command

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\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\shell\NoAddOns
    • MUIVerb = "@shdoclc.dll,-10241"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}
    • InfoTip = "????????"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\shell\NoAddOns
    • MUIVerb = "@shdoclc.dll,-10241"

Step 5

Restore these modified registry values

[ Learn More ]

Important:Editing the Windows Registry incorrectly can lead to irreversible system malfunction. Please do this only if you know how to or you can seek your system administrator's help. You may also check out this Microsoft article first before modifying your computer's registry.

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}
    • From: InfoTip = "@shdoclc.dll,-881"
      To: InfoTip = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}
    • From: LocalizedString = "@shdoclc.dll,-880"
      To: LocalizedString = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\InProcServer32
    • From: ThreadingModel = "Apartment"
      To: ThreadingModel = ""Apartment""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{871C5380-42A0-1069-A2EA-08002B30309D}\ShellFolder
    • From: Attributes = "0"
      To: Attributes = ""24""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}
    • From: LocalizedString = "????"
      To: LocalizedString = ""{random values}""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\InProcServer32
    • From: ThreadingModel = "Apartment"
      To: ThreadingModel = ""Apartment""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{1f4de370-d627-11d1-ba4f-00a0c91eedba}\ShellFolder
    • From: Attributes = "0"
      To: Attributes = ""20180000""

Step 6

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.
  • %User Profile%\Quick Launch\Launch Internet Explorer Browser.lnk
  • %Desktop%\Internet Explorer.lnk

Step 7

Scan your computer with your Trend Micro product to delete files detected as TROJ_STARTPA.SMP. 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.

Step 8

Restore deleted/modified files and/or registry entries from backup

*Note: Only Microsoft-related files/keys/values will be restored. If this malware/grayware also deleted registry keys/values related to programs that are not from Microsoft, please reinstall those programs on your computer.

    • %Start Menu%\Programs\Internet Explorer.lnk


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