Topics covered

Part I:
Part II:
Part III (here):
Related links:

Internet Explorer 6 hijacking Part III: Window Title,  Search Pages and miscellaneous entries

Go to Part I: Internet Options menu

Go to Part II: Home and blank pages

Topics on this page:

IE Window Title

IE Search Page and about:blank hijack

Summary

Entries affecting the user

Entries affecting the local computer

Miscellaneous entries:

 

 

IE Window Title

The registry key for IE Window Title (the text which is displayed on the top bar of your IE window after the webpage title) is:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Window Title
REG_SZ =

This value name is absent by default but IE will display Microsoft Internet Explorer. You can customise it by adding the name and value or it is branded by a company or it can be hijacked with a website title. It is conceivable that an entry in the corresponding HKLM registry key have the same effect but I've not seen it.

You can use the Group Policy editor to customise your window title in:

User Configuration\Windows Settings\Internet Explorer Maintenance\
Browser User Interface

Browser Title

Setting this external branding restriction in Windows XP Professional's Group Policy may stop it from being changed:

User Configuration\Administrative Templates\Windows Components\Internet Explorer\
Disable external branding of internet Explorer:
Enabled

The registry key is:

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Restrictions

NoExternalBranding
REG_DWORD: (1)

 

IE Search page and about:blank hijack

about:blank hijack

If the IE search page or the home page is hijacked with about:blank to direct to a search page, it could be a virus or a variant of CoolWebSearch: read the following note.

Note: if it is a version or variant of CoolWebSearch then you can get more information here as it is very hard to remove. You need the CoolWebShredder tool. The about:blank page has now been used too as part of CoolWebSearch. For other hijacked home sites you should search on the internet (especially this site) for more up to date specific fix. You usually find answers in forums or ask in forums. This is a general guide which should work in the vast majority of cases of hijacks other than CoolWebSearch or about:blank page hijacks.

Some about:blank viruses enter a hidden value data entry in this registry key (as well as non-hidden DLLs in system32 folder); normally there should be no data:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Windows
AppInit_DLLs
REG_SZ:

Other search page hijacks

The search page links to the search engine that you choose. The default keys are:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Search Page
REG_SZ = http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=iesearch

You can use Windows XP Professional's Group Policy editor to customise it in:

User Configuration\Windows Settings\Internet Explorer Maintenance\URLS
Important URLs

Setting this restriction in the Group Policy may lock it:

User Configuration\Administrative Templates\
Windows Components\Internet Explorer\
Search: Disable Search Customization: Enabled

The registry keys are:

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Restrictions

NoSearchCustomization
REG_DWORD (1)

It is possible to add the following subkey as hijack object or customisation; this is not present by default:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Default_Search_URL
REG_SZ =

The following default keys should remain unchanged after customisation for the user (which changes the HKCU key only) but can be hijacked too.

HKEY_LOCAL_MACHINE\Software\Microsoft\
Internet Explorer\Main

Default_Search_URL
REG_SZ = http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=_
iesearch
 
Search Page
REG_SZ = http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=_
iesearch

It is possible to hijack or customise search here; these are not necessarily present by default:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Search
CustomizeSearch
REG_SZ =

SearchAssistant
REG_SZ =

Default_Search_URL
REG_SZ =

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\SearchUrl
(Default)
REG_SZ =

 

These subkeys are present by default and their values are:

HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\URLSearchHooks
Default
REG_SZ =

{CFBFAE00-17A6-11D0-99CB-00C04FD64497}
REG_SZ =

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\URL\DefaultPrefix
Default
REG_SZ = http://

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\URL\Prefixes
home
REG_SZ = http://

www
REG_SZ = http://

 


Summary

A systematic approach to tackling IE hijacking

***For a specific home page or toolbar hijacking, search in Google first as there may well be a specific fix. Refer to my note for CoolWebSearch above.***

General approach:

1. Reset the home page in the IE, Tools, Internet Options, General page, Address bar, or Use Default or Blank.

If the bar is greyed out then go to step (5). If the hijacked home page reappears on reboot, carry on below. If the home page is locked, go to step (5). For toolbar hijacking, refer to the registry entries in the sections below.

For search page, use the Group Policy editor, or go to step (9).

2. In Task Manager, stop (End process) all non-essential running tasks. Find and delete any suspicious processes. Or go to Safe Mode and proceed to step (3). VERY IMPORTANT as otherwise they may not be eradicated.

3. Go through the registry manually to remove offending items. Try the Group Policy Editor in Windows XP Professional to reset the home and search pages.

4. Scan and remove viruses, worms, Trojans, spyware, adware thoroughly.

5. If the home page is locked, unlock it in the registry or Group Policy Editor.

6. If regedit is locked or "operation cancelled", unlock it first with the Group Policy Editor or other means (refer to my articles on this).

7. Disable autostart entries: search in the HKCU and HKLM Run registry keys and the Windows user (under your name) and All Users startup folders and delete any offending items.

8. Optional but advisable - delete all junk:
Windows temp files, IE temporary internet files, Typed URL list, cookies and history
.

9. If the above fails, try System Restore, restore from NTBackup, ASR (XP Professional) or Ghost and other software (e.g. Browser Hijack Blaster). The Startup List generated in HijackThis gives you a detailed analysis of all the startup hijack objects.

Afterwards, once you have cleaned up, to prevent it from happening again:

10. Lock your homepage (does not stop scripts from running).

11. Custom increase the IE security settings to higher than Medium (default) level or high (refer to my IE security article). Microsoft now recommends increasing IE security level to HIGH (link).  VERY IMPORTANT

12. Install all the critical Microsoft Windows and IE security patches. VERY IMPORTANT

13. Use another browser that does not use the IE core and thus more secure, e.g. Netscape/Mozilla/Firefox. STRONGLY RECOMMENDED

14. Use the Sun Java VM instead of the outdated and vulnerable Microsoft Java VM. If you insist on using the latter, at least update to the latest build 3810 (no more is expected to be released).

 

The registry keys

As you may realise by now, the two registry keys for the current user and local machine contain entries for the IE start page, search page, local page and the HKCU key only has an optional entry for window title. HijackThis will find these keys and Browser Hijack Blaster will also protect the home, search and local (default) pages (see Part II). The entries which direct IE to MSN can be removed if you wish.

Entries affecting the user (HKCU keys)

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Main
Local Page
REG_EXPAND_SZ = %SystemRoot%\System32\blank.htm

Search Page
REG_SZ = http://www.microsoft.com/isapi/redir.dll?prd=ie&ar=_
iesearch 

Start Page
REG_SZ =

(Most likely you would have customised this. The default is the same as in HKLM key for the link to MSN.)

Window title
REG_SZ =
(This is absent by default.)

 

Entries affecting the local computer (HKLM keys)

The other default settings are in the HKLM registry hive:

HKEY_LOCAL_MACHINE\Software\Microsoft\
Internet Explorer\Main
Default_Page_URL
REG_SZ = http://www.microsoft.com/isapi/_
redir.dll?prd=ie&pver=6&ar=msnhome

(The path is one line.)

Default_Search_URL
REG_SZ = http://www.microsoft.com/isapi/_
redir.dll?prd=ie&ar=iesearch

Local Page
REG_EXPAND_SZ =
%SystemRoot%\System32\blank.htm

Search Page
REG_SZ = http://www.microsoft.com/isapi/
redir.dll?prd=ie&ar=iesearch

Start Page
REG_SZ=
http://www.microsoft.com/isapi/redir.dll?prd=
{SUB_PRD}&clcid=(SUB_CLSID}&pver=_
{SUB_PVER}&ar=home

(The path is one line.)

 

Miscellaneous entries:

The following list of possible hijack object location is not exhaustive but is well worth checking. These changes can also be customised (branded) by the user or a company or the targets of viruses and Trojans. This list will be updated as necessary.


Legacy software key:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\WinOldApp
NoRealMode
Disabled

This is subkey not found in Win XP by default; it may be for old programmes or Windows versions and is the target for the JS_Offensive Trojan. Delete it if found.

 


Programme start up folders and keys:

Look through these start up registry keys methodically. You probably won't have them all; most are legacy keys and the keys with Policies are only created by Group Policy. The following keys are listed in the order of execution. The RunOnce, RunOnceEx and RunServicesOnce keys contain items which are meant to execute once only.

There're at least six HKLM and six HKCU registry keys responsible for startup items.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunServicesOnce
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunServices
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnceEx
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Policies\Explorer\Run
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
 

and:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Run
HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\Policies\Explorer\Run
HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnce
HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunOnceEx
HKEY_CURRENT_USER\SOFTWARE\Microsoft\
Windows\CurrentVersion\RunServices

 

Apart from registry startup keys, other possible locations for startup items include:

  • Per Computer logon scripts
  • Per Computer scheduled tasks
  • Per User logon scripts
  • Per User scheduled tasks
  • All Users' Startup folder (usually in C:\Documents and Settings\All Users\Start Menu\Programs\Startup)
  • Individual user's Startup folder (usually in P:\Documents and Settings\<username>\Start Menu\Programs\Startup)

Also check these suspicious entries in the registry entries:

Iexplore.exe
Internal
Internat.exe
Internet.url
ScanRegistry
TaskMonitor
SystemTray
LoadPowerProfile
regedit -s (or: regedit.exe -s)
any .bat, .dll, .hta, .exe, .js, .jse, .vbe, .vbs, .wsc, .wsf and .wsh entries

Delete any of the above names and values. Note that internat.exe is a file normally used for language input in older versions of Windows but it can be infected. The regedit -s entry is highly suspicious as it edits the registry silently on boot up.

In Explorer, look also in the Startup Folders in the user folder and All Users folder, both under the Start Menu, Programs.

You can also disable startup programs and processes in Windows XP's msconfig or other startup manager (e.g. Startup Control Panel) but it would be preferable to delete the offending entries at their source rather than just disabling them from execution.

***NEW*** Some hijackers now use dynamic link libraries (DLLs) which starts up and load in memory. This is very hard to detect and remove unless you know what to look for and how to stop it and un-register it. You might want to try deleting it in Safe Mode, or use some tools such as Killbox and Sysinternal's Process Explorer to trace what other files are involved.


IE Right click context menu extension

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\MenuExt

Any subkey under MenuExt would appear in the IE right click menu: e.g. download managers like Download Accelerator Plus and FlashGet. The commands are shortcuts linked to html files or programme flags. Sometimes these are not removed during programme un-installation and can be manually cleaned up.

Setting this restriction in Windows XP Pro's Group Policy would disable it:

User Configuration\Administrative Templates\Windows Components\Internet Explorer\Browser menus
Disable Context menu: Enabled

The registry key is:

HKEY_CURRENT_USER\Software\Policies\
Microsoft\Internet Explorer\Restrictions

NoBrowserContextMenu
REG_DWORD (1)

 


IE toolbar add-ons

Toolbar icon, button, extra toolbar, search assistant

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Extensions
{a long alphanumeric globally unique identifier (CLSID GUID) number}

Any {CLSID GUID} entry would be an add-on icon/button/toolbar/search assistant (more details here). If you find it here you also need to look elsewhere searching the same GUID number in the registry (more details here):

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Explorer Bars\{Hijack Object's CLSID GUID}
BarSize =

HKEY_CLASSES_ROOT\CLSID\{Hijack Object's CLSID GUID} (Default) = Menu Text String
InProcServer32
(Default) = DLL Pathname ThreadingModel=Apartment

Instance, CLSID
(Default) = {4D5C8C2A-D075-11D0-B416-00C04FB90376}

Instance, InitPropertyBag
Url = an HTML File

The HKEY_CLASSES_ROOT key is mapped to the HKEY_LOCAL_MACHINE\SOFTWARE\Classes key and a CLSID is a GUID that identifies a COM class object that is registered. So you'll find the same entries in both keys.

An example of CLSID GUID from a porn site can be found here.

This is related to the Alexa toolbar (more details here).

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Extensions\cmdmapping
\
{9d74677a-e227-40fb-9511-f7e92ea4083a}

There are many others which you can search (using the above key) on the internet if you don't know what they are.

The toolbar can also be customised via Windows XP Pro's Group Policy editor:

User Configuration, Windows Settings, Internet Explorer Maintenance, Browser User Interface: Browser Toolbar Customizations.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Extensions

Subkeys here add toolbar extensions.

This subkey is the Alexa toolbar  and the 'Tools'/'Show Related Links' menu item:
{c95fe080-8f5d-11d2-a20b-00aa003c157a}

These subkeys in GUID are installed by the JS.Fortnight.D Trojan:
{0B5F1910-F111-11d2-BB9E-00C04F7956B1} to
{0B5F1910-F111-11d2-BB9E-00C04F7956B5}

Toolbar background

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Toolbar
BackBitmap
REG_SZ

The BackBitmap points to an image file for adding a toolbar background; the same can be done also using third party programmes like TweakXP. The changes affects both IE, Outlook Express and Windows Explorer.

Toolbar and button customisation can be disabled in the Group Policy Editor:

HKEY_CURRENT_USER\Software\Microsoft\Windows\
CurrentVersion\Policies\Explorer:
NoBandCustomize
NoToolbarCustomize

Toolbar logo

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Toolbar
BrandBitmap
REG_SZ

BrandLeadIn
REG_DWORD

SmBrandBitmap
REG_SZ

SmBrandLeadIn
REG_DWORD

SmBrandHeight
REG_DWORD

Either setting would add a large or small animated logo in the top right corner of IE, OE and Explorer while the programme is busy. The graphic file needs to be a bitmap as vertical filmstrip of 38 or 22 (or any other size as long as it's smaller than the large image) pixels times the number of frames in pixels.

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\Toolbar

for per user setting (above) or per computer setting (below):

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet
Explorer\Main
BigBitmap
REG_SZ

SmallBitmap
REG_SZ

Either setting would add a large or small non-animated logo which appears while the programme is idle. The path points of a bitmap file of say 38x38 or 22x22 pixels.

This can also be done via TweakUI version 2.10 or the Group Policy editor:

User Configuration\Windows Settings\Internet Explorer Maintenance\Browser User Interface
Custom Logo

 


IE alternative search engine URL

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\SearchUrl
provider

There is no default value data so anything here is customised or hijacked. It is used by the JS.Fortnight.D Trojan to redirect the search to the Trojan's website. You can customise your alternative search engine here.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Internet Explorer\Search

CustomizeSearch
SearchAssistant

These are also used by the JS.Fortnight.D Trojan to redirect the search. Reset the data to About:blank if you find any entries you don't want. You can also customise your alternative search engine here to Google, for example.

***NEW*** Unfortunately the About:blank can also masquerade a search page hijack and may be part of CoolWebSearch.


IE Typed URL history

Sometimes when you delete the IE history some internet addresses remain in the address bar (this not the same as autocomplete or IE history); here you need to delete the entries in the registry:

HKEY_CURRENT_USER\Software\Microsoft\
Internet Explorer\TypedURLs

Delete the data on the right pane, leaving only the default name.

You can write a script file (bat or vbs) to clean the list regularly.

It is possible to prevent IE from storing this list, as part of disabling personalised menu, by setting a registry policy (source) but this would also affect other programmes that use personalised menus.

HKEY_CURRENT_USER\Software\Microsoft\
Windows\
CurrentVersion\Policies\Explorer\
NoInstrumentation
REG_DWORD = (1)

This can also be done in Windows XP Pro's Group Policy editor:

User Configuration\Administrative Templates\Start Menu and Taskbar
Turn off user tracking

Setting the following registry key is designed to prevent the drop-down menu of the Address bar from displaying the typed URLs when you start typing a URL. It displays an empty drop-down menu. But this would prevent the Start, Run dialogue's menu from displaying anything too.

HKEY_CURRENT_USER\Software\Microsoft\
Windows\
CurrentVersion\policies\Explorer
NoRecentDocsMenu
REG_BINARY = (01)

 


The hosts file

The hosts file may contain entries to redirect your search or as part of spyware. If you find suspicious hosts files in your system, e.g. in Windows\Help\ it should not be there. Check the contents of the hosts file in the Windows\system32\drivers\etc folder. This file is altered by some recent worm infections.

 


Third party add-ons

For some IE add-ons (e.g. search bars which you install intentionally or as hijack objects) there might be an entry in the Control Panel, Add or Remove Programs list so it is worth looking there first.

 


CoolWebSearch (CWS) hijacking

This is covered in detail here where there is a tool CWShredder to remove it. The author there says this hijack object is updated frequently so be sure to download the latest CWShredder. Note also that this might be associated with Trojans that exploit the ByteCode Verifier Vulnerability of the Microsoft Java VM in versions older than Build 5.0.3810. Therefore use the Sun Java VM instead.

 


Windows Extra logon window

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\
Windows\CurrentVersion\Winlogon
LegalNoticeCaption
LegalNoticeText

This is strictly speaking not in IE but comes up before Windows logon. If the entries are present in the registry a window appears during boot up before the logon (Welcome) screen with a caption title and text. You have to click OK to proceed to the logon screen. Sometimes this is used by companies to display their information but can also be a target for hijacking. This can be set using Xteq System XSetup.

 

Go to TOP

 

Reference

Browser extensions

Internet Explorer Branding

about:blank virus

 

Copyright © 2003-2004 by Kilian. All my articles including graphics are provided "as is" without warranties of any kind. I hereby disclaim all warranties with regard to the information provided. In no event shall I be liable for any damage of any kind whatsoever resulting from the information. The articles are provided in good faith and after some degree of verification but they may contain technical or typographical errors. Links to other web resources may be changed at any time and are beyond the control of the author. Articles may be added, removed, edited or improved at any time. No support is provided by the author.

This is not an official support page for HijackThis or other products mentioned. All the products mentioned are trademarks of their companies. Edit the registry at your own risk and back up first.

Last updated 13 Nov 2005