HijackThis Tutorial 2
HijackThis Tutorial 2
What is HijackThis?
| HijackThis is a program originally developed by Merijn Bellekom, a Dutch student studying chemistry and computer science. One of Merijn’s programs, Hijackthis, is an essential utility to help find and remove spyware, viruses, worms, trojans and other pests.This is a basic guide to understanding the HijackThis logs, what specific sections mean and some tips on reading it yourself. Although its best to have a knowledgeable person help you examine the Hijackthis log and decide what to remove, its helpful to have a basic understanding of what the different sections mean and how they work.In March 2007, Merijn sold Hijackthis to TrendMicro because he didnt have the time and energy to update it and support it. Trend Micro has incorporated many of Merijn’s changes, updates, and fixes and released a version 2 of Hijackthis. |
New Features
The newest feature of HijackThis 2.0 is a button called AnalyzeThis that will upload your HijackThis log to the TrendSecure website and compare it to other uploaded log files. Unfortunately I was hoping for more from this feature, although it does give you a rough estimate of the number of users that have a particular file in their logs as well. For the novice user however this doesnt explain WHAT the file does and if its really a threat or not. A better online tool to analyze the Hijackthis logs is found at http://www.hijackthis.de. There you can either cut and paste a copy of your HijackThis log or upload a log file from your computer to analyze. This information returned from the HijackThis.DE site is much more helpful in determining good and bad items in the log.
There appear to be other minor modifications as well.
Overview of items in the HijackThis logs
Each line in a HijackThis log starts with a section name. (For technical information on this, click ‘Info’ in the main window and scroll down. Highlight a line and click ‘More info on this item’.)
R0, R1, R2, R3 – IE Start & Search page
R0 – Changed registry value
R1 – Created registry value
R2 – Created registry key
R3 – Created extra registry value where only one should be
What it looks like:
R0 – HKCUSoftwareMicrosoftInternet ExplorerMain,Start Page=http://www.google.com/
R1 – HKLMSoftwareMicrosoftInternet ExplorerMain,Default_Page_URL=http://www.google.com/
R3 – Default URLSearchHook is missing
What to do:
If you recognize the URL at the end as your homepage or search engine, it’s OK. If you don’t, check it and have HijackThis fix it. In cases like a hijacker you may want to leave them til later but in general if you dont recognize it, fix it.
For the R3 items, always fix them unless it mentions a program you recognize.
F0, F1, F2, F3 – Autoloading programs
F0 – Changed inifile value
F1 – Created inifile value
F2 – Changed inifile value, mapped to Registry
F3 – Created inifile value, mapped to Registry
What it looks like:
F0 – system.ini: Shell=Explorer.exe Openme.exe
F1 – win.ini: run=hpfsched
What to do:
The F0 items are always bad, so fix them.
The F1 items are usually very old programs that are safe, so you should find some more info on the filename to see if it’s good or bad.
N1, N2, N3, N4 – Netscape/Mozilla Start & Search page
N1 – Change in prefs.js of Netscape 4.x
N2 – Change in prefs.js of Netscape 6
N3 – Change in prefs.js of Netscape 7
N4 – Change in prefs.js of Mozilla
What it looks like:
N1 – Netscape 4: user_pref(“browser.startup.homepage”, “www.google.com”); (C:Program FilesNetscapeUsersdefaultprefs.js)
N2 – Netscape 6: user_pref(“browser.startup.homepage”, “http://www.google.com”); (C:Documents and SettingsUserApplication DataMozillaProfilesdefaulto9t1tfl.sltprefs.js)
N2 – Netscape 6: user_pref(“browser.search.defaultengine”, “engine://C%3A%5CProgram%20Files%5CNetscape%206%5Csearchplugins%5CSBWeb_02.src”); (C:Documents and SettingsUserApplication DataMozillaProfilesdefaulto9t1tfl.sltprefs.js)
What to do:
Usually the Netscape and Mozilla homepage and search page are safe. They rarely get hijacked. Should you see an URL you don’t recognize as your homepage or search page, have HijackThis fix it.
O1 – Hosts file redirection
What it looks like:
O1 – Hosts: 216.177.73.139 auto.search.msn.com
O1 – Hosts: 216.177.73.139 search.netscape.com
O1 – Hosts: 216.177.73.139 ieautosearch
What to do:
This hijack will redirect the address to the right to the IP address to the left. If the IP does not belong to the address, you will be redirected to a wrong site everytime you enter the address. You can always have HijackThis fix these, unless you knowingly put those lines in your Hosts file.
O2 – Browser Helper Objects
What it looks like:
O2 – BHO: Yahoo! Companion BHO – {13F537F0-AF09-11d6-9029-0002B31F9E59} – C:PROGRAM FILESYAHOO!COMPANIONYCOMP5_0_2_4.DLL
O2 – BHO: AcroIEHlprObj Class – {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} – C:\Adobe\Acrobat 5.0\Acrobat\ActiveX\AcroIEHelper.ocx
O2 – BHO: (no name) – {724d43a9-0d85-11d4-9908-00400523e39a} – C:\Program Files\Siber Systems\AI RoboForm\RoboForm.dll
What to do:
If you don’t directly recognize a Browser Helper Object’s name, use TonyK’s BHO List to find it by the class ID (CLSID, the number between curly brackets) and see if it’s good or bad. In the BHO List, ‘X’ means spyware and ‘L’ means safe. Or Upload your Hijackthis log to the Online HijackThis Analyzer and see if its safe.
O3 – IE toolbars
What it looks like:
O3 – Toolbar: &Yahoo! Companion – {EF99BD32-C1FB-11D2-892F-0090271D4F88} – C:PROGRAM FILES\YAHOO!COMPANION\YCOMP5_0_2_4.DLL
O3 – Toolbar: Popup Eliminator – {86BCA93E-457B-4054-AFB0-E428DA1563E1} – C:PROGRAM FILES\POPUP ELIMINATOR\PETOOLBAR401.DLL (file missing)
O3 – Toolbar: &RoboForm – {724d43a0-0d85-11d4-9908-00400523e39a} – C:\Program Files\Siber Systems\AI RoboForm\RoboForm.dll
What to do:
If you don’t directly recognize a toolbar’s name, use TonyK’s Toolbar List to find it by the class ID (CLSID, the number between curly brackets) and see if it’s good or bad. In the Toolbar List, ‘X’ means spyware and ‘L’ means safe.
If it’s not on the list and the name seems a random string of characters and the file is somewhere in a folder named ‘Application Data’, it’s definitely bad, and you should have HijackThis fix it. Or Upload your Hijackthis log to the Online HijackThis Analyzer and see if its safe.
O4 – Autoloading programs from Registry
What it looks like:
O4 – HKLM..Run: [ScanRegistry] C:WINDOWSscanregw.exe /autorun
O4 – HKLM..Run: [SystemTray] SysTray.Exe
O4 – HKLM..Run: [ccApp] “C:Program FilesCommon FilesSymantec SharedccApp.exe”
O4 – Startup: Microsoft Office.lnk = C:Program FilesMicrosoft OfficeOfficeOSA9.EXE
What to do:
Use PacMan’s Startup List to find the entry and see if it’s good or bad.
O5 – IE Options not visible in Control Panel
What it looks like:
O5 – control.ini: inetcpl.cpl=no
What to do:
Unless you’ve knowingly hidden the icon from Control Panel, have HijackThis fix it.
O6 – IE Options access restricted by Administrator
What it looks like:
O6 – HKCUSoftwarePoliciesMicrosoftInternet ExplorerRestrictions present
What to do:
Unless you have the Spybot S&D option ‘Lock homepage from changes’ active, have HijackThis fix this.
O7 – Regedit access restricted by Administrator
What it looks like:
O7 – HKCUSoftwareMicrosoftWindowsCurrentVersionPoliciesSystem, DisableRegedit=1
What to do:
Always have HijackThis fix this.
O8 – Extra items in IE right-click menu
What it looks like:
O8 – Extra context menu item: &Google Search – res://C:WINDOWSDOWNLOADED PROGRAM FILESGOOGLETOOLBAR_EN_1.1.68-DELEON.DLL/cmsearch.html
O8 – Extra context menu item: Yahoo! Search – file:///C:Program FilesYahoo!Common/ycsrch.htm
What to do:
If you don’t recognize the name of the item in the right-click menu in IE, have HijackThis fix it.
O9 – Extra buttons on main IE toolbar, or extra items in IE ‘Tools’ menu
What it looks like:
O9 – Extra button: Messenger (HKLM)
O9 – Extra ‘Tools’ menuitem: Messenger (HKLM)
O9 – Extra button: AIM (HKLM)
What to do:
If you don’t recognize the name of the button or menuitem, have HijackThis fix it.
O10 – Winsock hijackers
What it looks like:
O10 – Hijacked Internet access by New.Net
O10 – Broken Internet access because of LSP provider ‘c:progra~1\common~2\toolbarcnmib.dll’ missing
O10 – Unknown file in Winsock LSP: c:program files\newton knows\vmain.dll
What to do:
It’s best to fix these using LSPFix from Cexx.org
O11 – Extra group in IE ‘Advanced Options’ window
What it looks like:
O11 – Options group: [CommonName] CommonName
What to do:
The only hijacker as of now that adds its own options group to the IE Advanced Options window is CommonName. So you can always have HijackThis fix this.
O12 – IE plugins
What it looks like:
O12 – Plugin for .spop: C:Program Files\Internet Explorer\Plugins\NPDocBox.dll
O12 – Plugin for .PDF: C:Program Files\Internet Explorer\PLUGINS\ppdf32.dll
What to do:
Most of the time these are safe. Only OnFlow adds a plugin here that you don’t want (.ofb).
O13 – IE DefaultPrefix hijack
What it looks like:
O13 – DefaultPrefix: http://www.pixpox.com/cgi-bin/click.pl?url=
O13 – WWW Prefix: http://prolivation.com/cgi-bin/r.cgi?
What to do:
These are always bad. Have HijackThis fix them.
O14 – ‘Reset Web Settings’ hijack
What it looks like:
O14 – IERESET.INF: START_PAGE_URL=http://www.searchalot.com
What to do:
If the URL is not the provider of your computer or your ISP, have HijackThis fix it.
O15 – Unwanted site in Trusted Zone
What it looks like:
O15 – Trusted Zone: http://www.badspyware.com
What to do:
Many different spyware and adware programs will add items to the Tursted Zone. In most cases, you’ll want to remove these with HijackThis.
O16 – ActiveX Objects (aka Downloaded Program Files)
What it looks like:
O16 – DPF: Yahoo! Chat – http://us.chat1.yimg.com/us.yimg.com/i/chat/applet/c381/chat.cab
O16 – DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) – http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab
What to do:
If you don’t recognize the name of the object, or the URL it was downloaded from, have HijackThis fix it. If the name or URL contains words like ‘dialer’, ‘casino’, ‘free_plugin’ etc, definitely fix it.
O17 – Lop.com domain hijacks
What it looks like:
O17 – HKLMSystemCCSServicesVxDMSTCP: Domain = aoldsl.net
O17 – HKLMSystemCCSServicesTcpipParameters: Domain = W21944.find-quick.com
O17 – HKLMSoftware..Telephony: DomainName = W21944.find-quick.com
O17 – HKLMSystemCCSServicesTcpip..{D196AB38-4D1F-45C1-9108-46D367F19F7E}: Domain = W21944.find-quick.com
What to do:
If the domain is not from your ISP or company network, have HijackThis fix it. You may want to run the Lop.com uninstaller as well to clean up misc Lop problems.
O18 – Extra protocols and protocol hijackers
What it looks like:
O18 – Protocol: relatedlinks – {5AB65DD4-01FB-44D5-9537-3767AB80F790} – C:PROGRA~1\COMMON~1\MSIETS\msielink.dll
O18 – Protocol: mctp – {d7b95390-b1c5-11d0-b111-0080c712fe82}
O18 – Protocol hijack: http – {66993893-61B8-47DC-B10D-21E0C86DD9C8}
What to do:
Only a few hijackers show up here. The known baddies are ‘cn’ (CommonName), ‘ayb’ (Lop.com) and ‘relatedlinks’ (Huntbar), you should have HijackThis fix those. Other things that show up are either not confirmed safe yet, or are hijacked by spyware. In the last case, have HijackThis fix it.
O19 – User style sheet hijack
What it looks like:
O19 – User style sheet: c:WINDOWS\Java\my.css
What to do:
In the case of a browser slowdown and frequent popups, have HijackThis fix this item if it shows up in the log.
O20 – AppInit_DLLs autorun Registry value, Winlogon Notify Registry keys
What it looks like:
O20 – Winlogon Notify: NavLogon – C:\WINDOWS\system32\NavLogon.dll
O20 – Winlogon Notify: WgaLogon – C:\WINDOWS\
O20 – Winlogon Notify: msupdate – C:\WINDOWS\SYSTEM32\msupdate32.dll
O20 – Winlogon Notify: dvd4free – C:\WINDOWS\SYSTEM32\dvd4free.dll
What to do:
Although some of these files are legitimate, many are spyware/adware hijacks that need to be removed. You can upload your log to the Hijackthis.de Online Analyzer
O21 – ShellServiceObjectDelayLoad (SSODL) autorun Registry key
What it looks like:
O21 – SSODL: WPDShServiceObj – {AAA288BA-9A4C-45B0-95D7-94D524869DB5} – C:\WINDOWS\system32\WPDShServiceObj.dll
O21 – SSODL: Trayz – {F5B7D0BE-5f02-4211-96DB-386DFA244900} – C:\WINDOWS\lghngdne.dll
What to do:
Not all entries are bad, but you should check Online Hijackthis Analyzer to verify before deleting an entry.
O22 – SharedTaskScheduler autorun Registry key
What it looks like:
O22 – SharedTaskScheduler: Browseui preloader – {438755C2-A8BA-11D1-B96B-00A0C90312E1} – C:\WINDOWS\system32\browseui.dll
O22 – SharedTaskScheduler: Component Categories cache daemon – {8C7461EF-2B13-11d2-BE35-3078302C2030} – C:\WINDOWS\system32\browseui.dll
What to do:
Again, many of these entries are good. The old version of Hijackthis 1.99 didnt check this section, while Hijack version 2 does. SmitFraud attacks usually hide here. Check the Online Hijackthis Analyzer if you are unsure before deleting.
O23 – Enumeration of NT Services
What it looks like:
O23 – Service: AlfaCleanerService – AlfaCleaner.com – C:\Program Files\AlfaCleaner\ACServer.exe
O23 – Service: Kerio Personal Firewall 4 (KPF4) – Kerio Technologies – D:\Program Files\Kerio\Personal Firewall 4\kpf4ss.exe
O23 – Service: Remote Procedure Call (RPC) Helper – Unknown – C:\WINDOWS\system32\sdkkv32.exe
What to do:
These are services which are loaded by the Service Control Manager in Windows 2000, XP, and Vista. They are generally loaded at bootup, before a user logs in. Firewalls and other important programs but rogue cleaning programs like AlfaCleaner may also load here. Check the Online Hijackthis Analyzer if you are unsure before deleting.