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Win32:Bubak [Rtk], Hijack.FolderOptions, krhwcot.sys

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2 replies to this topic

#1 andyk250


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  • Local time:08:59 PM

Posted 01 November 2010 - 09:26 AM

Hi there. I appear to be infected with some Malware. Avast! is identifying krhwcot.sys as a possible Win32:Bubak rootkit. From what I can tell, its primary purpose is link redirecting in internet browsers. It also sent some spam messages via my Facebook account. It has also disabled the "Folder Options" when viewing folders and made hidden files invisible by default. Last but not least, I am having periodic blue screens with "IRQL Not Less Or Equal" errors. So far, these screens appear too briefly for me to see the specific error listed.

I have run Avast!, Malwarebytes Anti-Malware, SuperAntiSpyware, Spybot, and AdAware, but none are able to resolve the problem. At best, they are detecting krhwcot.sys as a probable rootkit and the following registry value hijacking:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\nofolderoptions (Hijack.FolderOptions)

I'm running a Windows XP computer with Service Pack 3.

I'm assuming this is a new variation of some virus, so I am updating my anti-virus programs as often as possible (updating can trigger crashes too, depending on the program). Any help with this would be much appreciated, though.

Following is my DDS log. Attached is my GMER log. I could not run a complete scan of all files because my computer crashes midway through the process. This is unfortunate, so I have provided the scan of processes and such. krhwcot.sys definitely seems to be the culprit, but I have no idea how to remove it at this point.


DDS (Ver_10-10-21.02) - NTFSx86
Run by Andy at 10:56:09.29 on Fri 10/29/2010
Internet Explorer: 6.0.2900.5512
Microsoft Windows XP Professional 5.1.2600.3.1252.1.1033.18.997.240 [GMT -5:00]

AV: avast! antivirus 4.8.1368 [VPS 101029-1] *On-access scanning disabled* (Updated) {7591DB91-41F0-48A3-B128-1A293FD8233D}

============== Running Processes ===============

C:\WINDOWS\system32\svchost -k DcomLaunch
C:\WINDOWS\System32\svchost.exe -k netsvcs
C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
C:\Program Files\Lavasoft\Ad-Aware\AAWService.exe
C:\Program Files\Alwil Software\Avast4\ashServ.exe
C:\Program Files\Java\jre6\bin\jusched.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\Documents and Settings\Andy\Application Data\dmfaj.exe
C:\Program Files\Java\jre6\bin\jqs.exe
C:\Program Files\Nitro PDF\Reader\NitroPDFReaderDriverService.exe
C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
C:\Program Files\Lavasoft\Ad-Aware\AAWTray.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\WINDOWS\system32\svchost.exe -k imgsvc
C:\Documents and Settings\Andy\Application Data\Dropbox\bin\Dropbox.exe
C:\Documents and Settings\Andy\Desktop\dds.scr

============== Pseudo HJT Report ===============

uStart Page = hxxp://www.yahoo.com/
uSearch Page = hxxp://www.google.com
uSearch Bar = hxxp://www.google.com/ie
BHO: Spybot-S&D IE Protection: {53707962-6f74-2d53-2644-206d7942484f} - c:\program files\spybot - search &

TB: Foxit Toolbar: {d4027c7f-154a-4066-a1ad-4243d8127440} - c:\program files\ask.com\GenericAskToolbar.dll
TB: Google Toolbar: {2318c2b1-4965-11d4-9b18-009027a5cd4f} - c:\program files\google\google toolbar\GoogleToolbar_32.dll
uRun: [swg] "c:\program files\google\googletoolbarnotifier\GoogleToolbarNotifier.exe"
uRun: [bootstartx.exe] c:\bootstartx.exe\bootstartx.exe
uRun: [SpybotSD TeaTimer] c:\program files\spybot - search & destroy\TeaTimer.exe
mRun: [IgfxTray] c:\windows\system32\igfxtray.exe
mRun: [HotKeysCmds] c:\windows\system32\hkcmd.exe
mRun: [Persistence] c:\windows\system32\igfxpers.exe
mRun: [SkyTel] SkyTel.EXE
mRun: [Alcmtr] ALCMTR.EXE
mRun: [Adobe Reader Speed Launcher] "c:\program files\adobe\reader 9.0\reader\Reader_sl.exe"
mRun: [SunJavaUpdateSched] "c:\program files\java\jre6\bin\jusched.exe"
mRun: [NeroFilterCheck] c:\program files\common files\ahead\lib\NeroCheck.exe
mRun: [avast!] c:\progra~1\alwils~1\avast4\ashDisp.exe
mRun: [mownscxare.tmp] "c:\docume~1\andy\locals~1\temp\mownscxare.tmp"
mRun: [KernelFaultCheck] %systemroot%\system32\dumprep 0 -k
dRun: [bootstartx.exe] c:\bootstartx.exe\bootstartx.exe
StartupFolder: c:\docume~1\alluse~1\startm~1\programs\startup\adobeg~1.lnk - c:\program files\common

files\adobe\calibration\Adobe Gamma Loader.exe
StartupFolder: c:\docume~1\alluse~1\startm~1\programs\startup\micros~1.lnk - c:\program files\microsoft

uPolicies-explorer: NoFolderOptions = 1 (0x1)
mPolicies-system: EnableLUA = 0 (0x0)
IE: E&xport to Microsoft Excel - c:\progra~1\micros~2\office10\EXCEL.EXE/3000
IE: Google Sidewiki... - c:\program files\google\google

IE: {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe
IE: {FB5F1910-F110-11d2-BB9E-00C04F795683} - c:\program files\messenger\msmsgs.exe
IE: {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - {53707962-6F74-2D53-2644-206D7942484F} - c:\program files\spybot - search &

DPF: {8FFBE65D-2C9C-4669-84BD-5829DC0B603C} -

DPF: {CAFEEFAC-FFFF-FFFF-FFFF-ABCDEFFEDCBA} - hxxp://java.sun.com/update/1.6.0/jinstall-1_6_0_12-windows-i586.cab
TCP: {7F63A6BE-D547-41A2-B45F-F21DFCB12F41} =,
Notify: !SASWinLogon - c:\program files\superantispyware\SASWINLO.DLL
Notify: igfxcui - igfxdev.dll
SEH: SABShellExecuteHook Class: {5ae067d3-9afb-48e0-853a-ebb7f4a000da} - c:\program files\superantispyware\SASSEH.DLL

================= FIREFOX ===================

FF - ProfilePath - c:\docume~1\andy\applic~1\mozilla\firefox\profiles\1erf86ju.default\
FF - prefs.js: browser.search.selectedEngine - Google
FF - prefs.js: browser.startup.homepage - hxxp://www.yahoo.com/
FF - prefs.js: keyword.URL - hxxp://search.fast-find.net/?sid=10101067100&s=
FF - plugin: c:\documents and settings\andy\application data\facebook\npfbplugin_1_0_1.dll
FF - plugin: c:\documents and settings\andy\application data\facebook\npfbplugin_1_0_3.dll
FF - plugin: c:\program files\google\update\\npGoogleOneClick8.dll
FF - plugin: c:\program files\mozilla firefox\plugins\npFoxitReaderPlugin.dll
FF - HiddenExtension: Microsoft .NET Framework Assistant: {20a82645-c095-46ed-80e3-08825760534b} -

c:\windows\microsoft.net\framework\v3.5\windows presentation foundation\dotnetassistantextension\

FF - user.js: browser.search.selectedEngine - Google
FF - user.js: browser.search.order.1 - Google
FF - user.js: keyword.URL - hxxp://search.fast-find.net/?sid=10101067100&s=c:\program files\mozilla firefox\greprefs\all.js -

pref("network.IDN.whitelist.xn--mgbaam7a8h", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--fiqz9s", true); // Traditional
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--fiqs8s", true); // Simplified
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--j6w193g", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--mgberp4a5d4ar", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--mgberp4a5d4a87g", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--mgbqly7c0a67fbc", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--mgbqly7cvafr", true);
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--kpry57d", true); // Traditional
c:\program files\mozilla firefox\greprefs\all.js - pref("network.IDN.whitelist.xn--kprw13d", true); // Simplified

============= SERVICES / DRIVERS ===============

R1 aswSP;avast! Self Protection;c:\windows\system32\drivers\aswSP.sys [2009-11-27 114768]
R1 SASDIFSV;SASDIFSV;c:\program files\superantispyware\sasdifsv.sys [2010-2-17 12872]
R1 SASKUTIL;SASKUTIL;c:\program files\superantispyware\SASKUTIL.SYS [2010-5-10 67656]
R2 aswFsBlk;aswFsBlk;c:\windows\system32\drivers\aswFsBlk.sys [2009-11-27 20560]
R2 avast! Antivirus;avast! Antivirus;c:\program files\alwil software\avast4\ashServ.exe [2009-11-27 138680]
R2 Lavasoft Ad-Aware Service;Lavasoft Ad-Aware Service;c:\program files\lavasoft\ad-aware\AAWService.exe [2010-9-23 1357464]
R2 NitroReaderDriverReadSpool;NitroPDFReaderDriverCreatorReadSpool;c:\program files\nitro

pdf\reader\NitroPDFReaderDriverService.exe [2010-7-12 196912]
R3 avast! Mail Scanner;avast! Mail Scanner;c:\program files\alwil software\avast4\ashMaiSv.exe [2009-11-27 254040]
S2 gupdate;Google Update Service (gupdate);c:\program files\google\update\GoogleUpdate.exe [2010-2-15 135664]
S3 avast! Web Scanner;avast! Web Scanner;c:\program files\alwil software\avast4\ashWebSv.exe [2009-11-27 352920]
S3 Lavasoft Kernexplorer;Lavasoft helper driver;c:\program files\lavasoft\ad-aware\kernexplorer.sys [2010-9-23 15008]

=============== Created Last 30 ================

2010-10-28 18:54:59 -------- d-----w- C:\TDSSKiller_Quarantine
2010-10-28 18:02:45 15880 ----a-w- c:\windows\system32\lsdelete.exe
2010-10-28 17:39:41 95024 ----a-w- c:\windows\system32\drivers\SBREDrv.sys
2010-10-28 17:29:41 -------- d-----w- c:\docume~1\andy\locals~1\applic~1\Sunbelt Software
2010-10-28 17:29:12 -------- dc-h--w- c:\docume~1\alluse~1\applic~1\{E961CE1B-C3EA-4882-9F67-F859B555D097}
2010-10-28 17:28:31 -------- d-----w- c:\program files\Lavasoft
2010-10-28 16:23:19 -------- d-----w- c:\program files\Trend Micro
2010-10-28 15:49:34 -------- d-----w- c:\program files\Spybot - Search & Destroy
2010-10-28 15:49:34 -------- d-----w- c:\docume~1\alluse~1\applic~1\Spybot - Search & Destroy
2010-10-28 14:26:49 65536 ----a-w- c:\docume~1\andy\applic~1\taps.exe
2010-10-28 14:26:48 175104 ----a-w- c:\docume~1\andy\applic~1\dmfaj.exe
2010-10-28 13:53:43 -------- d-----w- c:\docume~1\andy\applic~1\SUPERAntiSpyware.com
2010-10-28 13:53:43 -------- d-----w- c:\docume~1\alluse~1\applic~1\SUPERAntiSpyware.com
2010-10-28 13:50:19 -------- d-----w- c:\program files\SUPERAntiSpyware
2010-10-27 20:09:27 147120 ----a-w- c:\windows\afuraran.dll
2010-10-27 20:08:31 -------- d-----w- c:\docume~1\alluse~1\applic~1\Update
2010-10-27 20:08:21 763904 ----a-w- c:\windows\system32\drivers\krhwcot.sys
2010-10-27 20:07:50 53248 ---ha-w- c:\windows\mstihone.dll
2010-10-27 20:07:34 53248 ---ha-w- c:\windows\system32\mstihone.dll
2010-10-05 19:24:53 -------- d-----w- c:\docume~1\alluse~1\applic~1\vsosdk
2010-10-05 13:12:17 -------- d-----w- c:\program files\DVDFab 8

==================== Find3M ====================

2010-10-18 14:35:35 1901 ----a-w- c:\windows\panose.bin
2010-09-18 17:23:26 974848 ----a-w- c:\windows\system32\mfc42u.dll
2010-09-18 06:53:25 974848 ----a-w- c:\windows\system32\mfc42.dll
2010-09-18 06:53:25 954368 ----a-w- c:\windows\system32\mfc40.dll
2010-09-18 06:53:25 953856 ----a-w- c:\windows\system32\mfc40u.dll
2010-09-09 14:16:31 667136 ----a-w- c:\windows\system32\wininet.dll
2010-09-09 14:16:30 61952 ----a-w- c:\windows\system32\tdc.ocx
2010-09-09 14:16:29 81920 ----a-w- c:\windows\system32\ieencode.dll
2010-09-08 16:49:49 369664 ----a-w- c:\windows\system32\html.iec
2010-09-01 11:51:14 285824 ----a-w- c:\windows\system32\atmfd.dll
2010-08-31 13:42:52 1852800 ----a-w- c:\windows\system32\win32k.sys
2010-08-27 08:02:29 119808 ----a-w- c:\windows\system32\t2embed.dll
2010-08-27 05:57:43 99840 ----a-w- c:\windows\system32\srvsvc.dll
2010-08-26 12:52:45 5120 ----a-w- c:\windows\system32\xpsp4res.dll
2010-08-23 16:12:04 617472 ----a-w- c:\windows\system32\comctl32.dll
2010-08-17 13:17:06 58880 ----a-w- c:\windows\system32\spoolsv.exe
2010-08-16 08:45:00 590848 ----a-w- c:\windows\system32\rpcrt4.dll

============= FINISH: 11:08:39.12 ===============

Attached File  ark.txt   8.26KB   0 downloads

I find it interesting too that this virus seems to be fairly new, and yet also seems to not have been addressed by virus definitions yet. What is the typical turnover between a virus being found and a "vaccination" being made for it?

EDIT: Posts merged ~BP

Edited by Budapest, 01 November 2010 - 04:15 PM.

BC AdBot (Login to Remove)


#2 Casey_boy


    Bleeping physicist

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  • Local time:02:59 AM

Posted 08 November 2010 - 05:02 PM

Hello and welcome to Bleeping Computer

We apologize for the delay in responding to your request for help. Here at Bleeping Computer we get overwhelmed at times, and we are trying our best to keep up. Please note that your topic was not intentionally overlooked. Our mission is to help everyone in need, but sometimes it takes just a little longer to get to every request for help. No one is ignored here.

If you have since resolved the original problem you were having, we would appreciate you letting us know. If not please perform the following steps below so we can have a look at the current condition of your machine.

If you have not done so, include a clear description of the problems you're having, along with any steps you may have performed so far.

Upon completing the steps below another staff member will review and take the steps necessary with you to get your machine back in working order clean and free of malware.

If you have already posted a DDS log, please do so again, as your situation may have changed.
Use the 'Add Reply' and add the new log to this thread.

Thanks and again sorry for the delay.

We need to see some information about what is happening in your machine. Please perform the following scan:
  • Download DDS by sUBs from one of the following links. Save it to your desktop.
  • Double click on the DDS icon, allow it to run.
  • A small box will open, with an explaination about the tool. No input is needed, the scan is running.
  • Notepad will open with the results.
  • Follow the instructions that pop up for posting the results.
  • Close the program window, and delete the program from your desktop.
Please note: You may have to disable any script protection running if the scan fails to run. After downloading the tool, disconnect from the internet and disable all antivirus protection. Run the scan, enable your A/V and reconnect to the internet.

Information on A/V control HERE

We also need a new log from the GMER anti-rootkit scanner. Please first disable any CD emulation programs using the steps found in this topic:

Why we request you disable CD Emulation when receiving Malware Removal Advice

Then create another GMER log and post it as an attachment to the reply where you post your new DDS log. Instructions on how to properly create a GMER log can be found here:

How to create a GMER log


If I have been helping you and I do not reply within 48hours, feel free to send me a PM.

* My Website * Am I Infected? * Malware Removal Help * If you'd like to say thanks *

#3 SpySentinel


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Posted 14 November 2010 - 03:10 PM

Due to lack of feedback, this topic has been closed.

If you need this topic reopened, please send me a PM.

This applies only to the original topic starter. Everyone else please begin a New Topic.
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