TROJ_STARTP.SMHO


 ALIASES:

Trojan:Win32/Startpage.OR (Microsoft); StartPage-FAB!D346EC409CA9 (McAfee); Trojan.Gen (Symantec); Trojan.Win32.Pasta.pit (Kaspersky); Trojan.Win32.Generic!BT (Sunbelt); Trojan.Generic.KDV.376451 (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:

821,787 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

10 Apr 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.

Other System Modifications

This Trojan modifies the following file(s):

  • %System%\drivers\etc\hosts
  • %Start Menu%\Programs\Internet Explorer.lnk

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

  • %Desktop%\Internet Explorer.url
  • %Desktop%\ÌÔ±¦Íø.lnk
  • %Desktop%\Internet Explorer.html
  • %Desktop%\360°²È«ÎÀÊ¿.lnk
  • %Desktop%\360Èí¼þ¹Ü¼Ò.lnk
  • %Desktop%\360ɱ¶¾.lnk
  • %Desktop%\ÈðÐÇɱ¶¾Èí¼þ.lnk
  • %Desktop%\ÐÞ¸´ÈðÐÇÈí¼þ.lnk
  • %Desktop%\Õ˺ű£ÏÕ¹ñ.lnk
  • %Start Menu%\Internet Explorer.url
  • %Start Menu%\ÌÔ±¦Íø.lnk
  • %Start Menu%\Internet Explorer.html
  • %Start Menu%\Programs\Internet Explorer.url
  • %Start Menu%\Programs\ÌÔ±¦Íø.lnk
  • %Start Menu%\Programs\Internet Explorer.html
  • %User Profile%\Quick Launch\Internet Explorer.url
  • %User Profile%\Quick Launch\ÌÔ±¦Íø.lnk
  • %User Profile%\Quick Launch\Internet Explorer.html
  • %User Profile%\Quick Launch\Æô¶¯ Internet Explorer ä¯ÀÀÆ÷.lnk
  • %User Profile%\Quick Launch\ÈðÐÇɱ¶¾Èí¼þ.lnk
  • %User Profile%\360se\360se_s.ini
  • %User Profile%\×ÀÃæ\Internet Explorer.lnk
  • %User Profile%\×ÀÃæ\ÌÔ±¦É̳Ç.lnk
  • %System%\drivers\etc\hosts

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

It adds the following registry keys:

HKEY_CLASSES_ROOT\PlayFlashDXA

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
DefaultIcon

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
Shell\ÊôÐÔ(&R)\Command

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
Shell\ɾ³ý(&D)\Command

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
Shell\ÖØÃüÃû(&M)\Command

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
Shell\Open(&O)\Command

HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\
ShellFolder

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Desktop\NameSpace\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}

It adds the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
ShowSuperHidden = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
PlayFlashDXA
1 = "13336"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
PlayFlashDXA
cdafile2 = "227a"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
PlayFlashDXA
9 = "0"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
PlayFlashDXA
9 = "1"

HKEY_LOCAL_MACHINE\SOFTWARE\Classes\
CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\ShellFolder
Attributes = "0"

It modifies the following registry entries:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced
SuperHidden = "0"

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Start Page = "http://www.{BLOCKED}e.com"

(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome.)

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Main
Start Page = "http://www.{BLOCKED}e.com"

(Note: The default value data of the said registry entry is http://www.microsoft.com/isapi/redir.dll?prd={SUB_PRD}&clcid={SUB_CLSID}&pver={SUB_PVER}&ar=home.)

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 = "0"

It deletes the following registry keys:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
SHOWALL

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\SuperHidden

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\HideFileExt

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\TypedUrls

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden\
NOHIDDEN

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Explorer\
Advanced\Folder\Hidden

Dropping Routine

This Trojan drops the following files:

  • %System%\msscp.reg
  • %Program Files%\Common Files\System\taobao.ico
  • D:\360\svchost.exe
  • %Windows%\web\Index.html
  • %Start Menu%\Internet Explorer.lnk
  • %User Profile%\Quick Launch\Internet Explorer.lnk
  • %Favorites%\Ãâ·Ñ¿´µçÓ°.url
  • %Favorites%\ÌÔ±¦Íø£¡.url

(Note: %System% is the Windows system folder, which is usually C:\Windows\System32.. %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).. %Windows% is the Windows folder, which is usually C:\Windows.. %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.. %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.. %Favorites% is the current user's Favorites folder, which is usually C:\Documents and Settings\{user name}\Favorites on Windows 2000, XP, and Server 2003, or C:\Users\{user name}\Favorites 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_CLASSES_ROOT
    • PlayFlashDXA
  • In HKEY_CLASSES_ROOT\CLSID
    • {F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}
    • DefaultIcon
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\Shell\ÊôÐÔ(&R)
    • Command
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\Shell\ɾ³ý(&D)
    • Command
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\Shell\ÖØÃüÃû(&M)
    • Command
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\Shell\Open(&O)
    • Command
  • In HKEY_CLASSES_ROOT\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}
    • ShellFolder
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace
    • {F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • ShowSuperHidden = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\PlayFlashDXA
    • 1 = "13336"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\PlayFlashDXA
    • cdafile2 = "227a"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\PlayFlashDXA
    • 9 = "0"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\PlayFlashDXA
    • 9 = "1"
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{F3CA57DF-C5DA-11CF-8F28-00AA0060FD42}\ShellFolder
    • Attributes = "0"

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_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
    • SuperHidden = "0"
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main
    • From: Start Page = "http://www.{BLOCKED}e.com"
      To: Start Page = ""http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome""
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Main
    • From: Start Page = "http://www.{BLOCKED}e.com"
      To: Start Page = ""http://www.microsoft.com/isapi/redir.dll?prd={SUB_PRD}&clcid={SUB_CLSID}&pver={SUB_PVER}&ar=home""

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.
  • %System%\msscp.reg
  • %Program Files%\Common Files\System\taobao.ico
  • D:\360\svchost.exe
  • %Windows%\web\Index.html
  • %Start Menu%\Internet Explorer.lnk
  • %User Profile%\Quick Launch\Internet Explorer.lnk
  • %Favorites%\Ãâ·Ñ¿´µçÓ°.url
  • %Favorites%\ÌÔ±¦Íø£¡.url

Step 7

Scan your computer with your Trend Micro product to delete files detected as TROJ_STARTP.SMHO. 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.

    • %System%\drivers\etc\hosts
    • %Start Menu%\Programs\Internet Explorer.lnk

Step 9

Restore this file from backup only Microsoft-related files will be restored. If this malware/grayware also deleted files related to programs that are not from Microsoft, please reinstall those programs on you computer again.

  • %Desktop%\Internet Explorer.url
  • %Desktop%\ÌÔ±¦Íø.lnk
  • %Desktop%\Internet Explorer.html
  • %Desktop%\360°²È«ÎÀÊ¿.lnk
  • %Desktop%\360Èí¼þ¹Ü¼Ò.lnk
  • %Desktop%\360ɱ¶¾.lnk
  • %Desktop%\ÈðÐÇɱ¶¾Èí¼þ.lnk
  • %Desktop%\ÐÞ¸´ÈðÐÇÈí¼þ.lnk
  • %Desktop%\Õ˺ű£ÏÕ¹ñ.lnk
  • %Start Menu%\Internet Explorer.url
  • %Start Menu%\ÌÔ±¦Íø.lnk
  • %Start Menu%\Internet Explorer.html
  • %Start Menu%\Programs\Internet Explorer.url
  • %Start Menu%\Programs\ÌÔ±¦Íø.lnk
  • %Start Menu%\Programs\Internet Explorer.html
  • %User Profile%\Quick Launch\Internet Explorer.url
  • %User Profile%\Quick Launch\ÌÔ±¦Íø.lnk
  • %User Profile%\Quick Launch\Internet Explorer.html
  • %User Profile%\Quick Launch\Æô¶¯ Internet Explorer ä¯ÀÀÆ÷.lnk
  • %User Profile%\Quick Launch\ÈðÐÇɱ¶¾Èí¼þ.lnk
  • %User Profile%\360se\360se_s.ini
  • %User Profile%\×ÀÃæ\Internet Explorer.lnk
  • %User Profile%\×ÀÃæ\ÌÔ±¦É̳Ç.lnk
  • %System%\drivers\etc\hosts

Step 10

Restore these deleted registry keys/values from backup

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

  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden
    • SHOWALL
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder
    • SuperHidden
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder
    • HideFileExt
  • In HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer
    • TypedUrls
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder\Hidden
    • NOHIDDEN
  • In HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Advanced\Folder
    • Hidden


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