Trojan.Win32.MALREP.THOABAAI

 Analysis by: Henry Alarcon Jr.

 ALIASES:

Trojan.MalPack.GS (Malwarebytes), W32/Kryptik.GPMP!tr (Fortinet), Trojan-Ransom.Downloader.Stop (Ikarus)

 PLATFORM:

Windows

 OVERALL RISK RATING:
 DAMAGE POTENTIAL:
 DISTRIBUTION POTENTIAL:
 REPORTED INFECTION:
 INFORMATION EXPOSURE:

  • Threat Type: Trojan

  • Destructiveness: No

  • Encrypted: No

  • In the wild: Yes

  OVERVIEW

Infection Channel:

Dropped by other malware


This Trojan may be downloaded from remote sites by other malware.

It adds certain registry entries to disable the Task Manager. This action prevents users from terminating the malware process, which can usually be done via the Task Manager.

It modifies the affected system's HOSTS files. This prevents users from accessing certain websites.

  TECHNICAL DETAILS

File Size:

284,160 bytes

File Type:

EXE

Memory Resident:

No

Initial Samples Received Date:

21 Jan 2019

Payload:

Displays graphics/image, Modifies HOSTS file

Arrival Details

This Trojan may be downloaded from remote site(s) by the following malware:

Installation

This Trojan drops and executes the following files:

  • %AppDataLocal%/script.ps1 ← powershell scripts
  • %User Temp%/delself.bat ← batch file to remove itself in the system.

(Note: %AppDataLocal% is the Local Application Data folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Application Data on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).. %User Temp% is the current user's Temp folder, which is usually C:\Documents and Settings\{user name}\Local Settings\Temp on Windows 2000(32-bit), XP, and Server 2003(32-bit), or C:\Users\{user name}\AppData\Local\Temp on Windows Vista, 7, 8, 8.1, 2008(64-bit), 2012(64-bit) and 10(64-bit).)

It adds the following processes:

  • powershell -Command Set-ExecutionPolicy -Scope CurrentUser RemoteSigned
  • powershell -NoProfile -ExecutionPolicy Bypass -Command "& {Start-Process PowerShell -ArgumentList '-NoProfile -ExecutionPolicy Bypass -File ""C:\Users\admin\AppData\Local\script.ps1""' -Verb RunAs}"
  • "C:\Program Files\Windows Defender\mpcmdrun.exe" -removedefinitions -all
  • cmd.exe /C "%UserTemp%\delfself.bat"

Other System Modifications

This Trojan adds the following registry entries to disable the Task Manager:

HKEY_CURRENT_USER\Software\Microsoft\
Windows\CurrentVersion\Policies\
System
DisableTaskmgr = 1

HOSTS File Modification

This Trojan modifies the affected system's HOSTS files to prevent a user from accessing the following websites:

  • ds.download.windowsupdate.com
  • www.update.microsoft.com
  • download.windowsupdate.com
  • fe2.update.microsoft.com
  • whoer.net
  • www.whoer.net
  • windowsupdate.com
  • www.windowsupdate.com
  • microsoft.com
  • www.microsoft.com
  • www.windowsupdate.com
  • windowsupdate.com
  • www.microsoft.com
  • www.360totalsecurity.com
  • 360totalsecurity.com
  • www.gratissoftwaresite.com
  • gratissoftwaresite.com
  • tweakers.net
  • www.tweakers.net
  • www.avg.com
  • avg.com
  • www.bestevirusscanner.net
  • bestevirusscanner.net
  • www.consumentenbond.nl
  • consumentenbond.nl
  • cheaplicensing.com
  • www.cheaplicensing.com
  • global.ahnlab.com
  • www.global.ahnlab.com
  • www.ahnlab.com
  • ahnlab.com
  • downloads.tomsguide.com
  • www.downloads.tomsguide.com
  • www.download82.com
  • download82.com
  • download.cnet.com
  • www.download.cnet.com
  • www.avast.com
  • avast.com
  • support.avast.com
  • www.support.avast.com
  • www.consumentenbond.com
  • consumentenbond.com
  • www.goedkoopsteantivirus.com
  • goedkoopsteantivirus.com
  • www.toptenreviews.com
  • toptenreviews.com
  • www.antivirus.nl
  • antivirus.nl
  • www.bol.com
  • bol.com
  • www.avira.com
  • avira.com
  • www.bitdefender.com
  • bitdefender.com
  • licentie2go.com
  • www.licentie2go.com
  • www.bullguard.com
  • bullguard.com
  • www.kpn.com
  • kpn.com
  • virusscanner.software
  • www.virusscanner.software
  • www.comodo.com
  • comodo.com
  • www.drweb.com
  • drweb.com
  • download.drweb.com
  • www.download.drweb.com
  • vms.drweb.com
  • www.vms.drweb.com
  • alternativeto.ne
  • www.alternativeto.ne
  • softonic.com
  • www.softonic.com
  • www.softpedia.com
  • softpedia.com
  • www.flipkart.com
  • flipkart.com
  • virustotal.com
  • www.virustotal.com
  • www.emsisoft.com
  • emsisoft.com
  • www.antimalwaresoftware.com
  • antimalwaresoftware.com
  • www.pcwebplus.com
  • pcwebplus.com
  • www.pcmag.com
  • pcmag.com
  • www.eset.com
  • eset.com
  • www.surfspot.com
  • surfspot.com
  • www.topantivirus.com
  • topantivirus.com
  • www.techzine.com
  • techzine.com
  • www.eset.com
  • eset.com
  • www.fortinet.com
  • fortinet.com
  • fortiguard.com
  • www.fortiguard.com
  • forticlient.com
  • www.forticlient.com
  • www.kpn.com
  • kpn.com
  • www.kaspersky.com
  • kaspersky.com
  • www.consumentenbond.com
  • consumentenbond.com
  • www.surfspot.com
  • surfspot.com
  • www.topreviews.com
  • topreviews.com
  • www.amecomputers.com
  • amecomputers.com
  • www.instantsoftware.com
  • instantsoftware.com
  • www.malwarebytes.com
  • malwarebytes.com
  • www.malwarebytes.org
  • malwarebytes.org
  • download.cnet.com
  • www.download.cnet.com
  • www.bleepingcomputer.com
  • bleepingcomputer.com
  • www.majorgeeks.com
  • majorgeeks.com
  • www.seniorweb.com
  • seniorweb.com
  • www.amazon.com
  • amazon.com
  • www.techspot.com
  • techspot.com
  • filehippo.com
  • www.filehippo.com
  • www.idealsoftware.com
  • idealsoftware.com
  • uptodown.com
  • www.uptodown.com
  • www.mcafee.com
  • mcafee.com
  • home.mcafee.com
  • www.home.mcafee.com
  • www.coolblue.com
  • coolblue.com
  • www.pcmag.com
  • pcmag.com
  • www.sky.com
  • sky.com
  • norton.com
  • www.norton.com
  • www.kieskeurig.com
  • kieskeurig.com
  • internetsecurity.xfinity.com
  • www.internetsecurity.xfinity.com
  • www.symantec.com
  • symantec.com
  • www.campusshop.com
  • campusshop.com
  • www.pandasecurity.com
  • pandasecurity.com
  • www.paradigit.com
  • paradigit.com
  • www.sophos.com
  • sophos.com
  • home.sophos.com
  • www.home.sophos.com
  • sophos.virtualsecurity.com
  • www.sophos.virtualsecurity.com
  • www.gratissoftware.com
  • gratissoftware.com
  • www.seniorweb.com
  • seniorweb.com
  • www.softwareadvice.com
  • softwareadvice.com
  • www.symantec.com
  • symantec.com
  • hostedendpoint.spn.com
  • www.hostedendpoint.spn.com
  • www.g2crowd.com
  • g2crowd.com
  • www.trendmicro.com
  • trendmicro.com
  • www.goedkoopsteantivirus.com
  • goedkoopsteantivirus.com
  • download.cnet.com
  • www.download.cnet.com
  • www.ign.com
  • ign.com
  • www.trusteer.com
  • trusteer.com
  • my.webrootanywhere.com
  • www.my.webrootanywhere.com
  • www.webroot.com
  • webroot.com
  • www.techradar.com
  • techradar.com
  • support.microsoft.com
  • www.support.microsoft.com
  • www.microsoft.com
  • microsoft.com
  • pulse.microsoft.com
  • www.pulse.microsoft.com
  • pcmweb.com
  • www.pcmweb.com
  • www.security.com
  • security.com
  • ccm.net
  • www.ccm.net
  • www.enigmasoftware.com
  • enigmasoftware.com
  • howtoremove.guide
  • www.howtoremove.guide
  • www.2-viruses.com
  • 2-viruses.com
  • www.2-spyware.com
  • 2-spyware.com
  • sensorstechforum.com
  • www.sensorstechforum.com
  • greatis.com
  • www.greatis.com
  • www.pchubs.com
  • pchubs.com
  • www.pcrisk.com
  • pcrisk.com
  • www.malware-board.com
  • malware-board.com
  • pcthreatskiller.com
  • www.pcthreatskiller.com
  • pcfixhelp.net
  • www.pcfixhelp.net
  • stepsforkillingthreats.com
  • www.stepsforkillingthreats.com
  • www.removemalwarevirus.com
  • removemalwarevirus.com
  • spyware-techie.com
  • www.spyware-techie.com
  • anti-spyware-101.com
  • www.anti-spyware-101.com
  • www.removeallvirus.com
  • removeallvirus.com
  • www.pcthreat.com
  • pcthreat.com
  • www.pcinfectionsupport.com
  • pcinfectionsupport.com
  • www.howtouninstallpcmalware.com
  • howtouninstallpcmalware.com
  • computerprotectionpro.com
  • www.computerprotectionpro.com

Other Details

This Trojan displays the following images:

  • fake Windows update

  SOLUTION

Minimum Scan Engine:

9.850

FIRST VSAPI PATTERN FILE:

14.764.05

FIRST VSAPI PATTERN DATE:

21 Jan 2019

VSAPI OPR PATTERN File:

14.765.00

VSAPI OPR PATTERN Date:

22 Jan 2019

Step 1

Before doing any scans, Windows 7, Windows 8, Windows 8.1, and Windows 10 users must disable System Restore to allow full scanning of their computers.

Step 2

Note that not all files, folders, and registry keys and entries are installed on your computer during this malware's/spyware's/grayware's execution. This may be due to incomplete installation or other operating system conditions. If you do not find the same files/folders/registry information, please proceed to the next step.

Step 3

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\Policies\System
    • DisableTaskmgr = 1

Step 4

Identify and terminate files detected as Trojan.Win32.MALREP.THOABAAI

[ Learn More ]
  1. Windows Task Manager may not display all running processes. In this case, please use a third-party process viewer, preferably Process Explorer, to terminate the malware/grayware/spyware file. You may download the said tool here.
  2. If the detected file is displayed in either Windows Task Manager or Process Explorer but you cannot delete it, restart your computer in safe mode. To do this, refer to this link for the complete steps.
  3. If the detected file is not displayed in either Windows Task Manager or Process Explorer, continue doing the next steps.

Step 5

Remove these strings added by the malware/grayware/spyware in the HOSTS file

[ Learn More ]
     
    • ds.download.windowsupdate.com
    • www.update.microsoft.com
    • download.windowsupdate.com
    • fe2.update.microsoft.com
    • whoer.net
    • www.whoer.net
    • windowsupdate.com
    • www.windowsupdate.com
    • microsoft.com
    • www.microsoft.com
    • www.windowsupdate.com
    • windowsupdate.com
    • www.microsoft.com
    • www.360totalsecurity.com
    • 360totalsecurity.com
    • www.gratissoftwaresite.com
    • gratissoftwaresite.com
    • tweakers.net
    • www.tweakers.net
    • www.avg.com
    • avg.com
    • www.bestevirusscanner.net
    • bestevirusscanner.net
    • www.consumentenbond.nl
    • consumentenbond.nl
    • cheaplicensing.com
    • www.cheaplicensing.com
    • global.ahnlab.com
    • www.global.ahnlab.com
    • www.ahnlab.com
    • ahnlab.com
    • downloads.tomsguide.com
    • www.downloads.tomsguide.com
    • www.download82.com
    • download82.com
    • download.cnet.com
    • www.download.cnet.com
    • www.avast.com
    • avast.com
    • support.avast.com
    • www.support.avast.com
    • www.consumentenbond.com
    • consumentenbond.com
    • www.goedkoopsteantivirus.com
    • goedkoopsteantivirus.com
    • www.toptenreviews.com
    • toptenreviews.com
    • www.antivirus.nl
    • antivirus.nl
    • www.bol.com
    • bol.com
    • www.avira.com
    • avira.com
    • www.bitdefender.com
    • bitdefender.com
    • licentie2go.com
    • www.licentie2go.com
    • www.bullguard.com
    • bullguard.com
    • www.kpn.com
    • kpn.com
    • virusscanner.software
    • www.virusscanner.software
    • www.comodo.com
    • comodo.com
    • www.drweb.com
    • drweb.com
    • download.drweb.com
    • www.download.drweb.com
    • vms.drweb.com
    • www.vms.drweb.com
    • alternativeto.ne
    • www.alternativeto.ne
    • softonic.com
    • www.softonic.com
    • www.softpedia.com
    • softpedia.com
    • www.flipkart.com
    • flipkart.com
    • virustotal.com
    • www.virustotal.com
    • www.emsisoft.com
    • emsisoft.com
    • www.antimalwaresoftware.com
    • antimalwaresoftware.com
    • www.pcwebplus.com
    • pcwebplus.com
    • www.pcmag.com
    • pcmag.com
    • www.eset.com
    • eset.com
    • www.surfspot.com
    • surfspot.com
    • www.topantivirus.com
    • topantivirus.com
    • www.techzine.com
    • techzine.com
    • www.eset.com
    • eset.com
    • www.fortinet.com
    • fortinet.com
    • fortiguard.com
    • www.fortiguard.com
    • forticlient.com
    • www.forticlient.com
    • www.kpn.com
    • kpn.com
    • www.kaspersky.com
    • kaspersky.com
    • www.consumentenbond.com
    • consumentenbond.com
    • www.surfspot.com
    • surfspot.com
    • www.topreviews.com
    • topreviews.com
    • www.amecomputers.com
    • amecomputers.com
    • www.instantsoftware.com
    • instantsoftware.com
    • www.malwarebytes.com
    • malwarebytes.com
    • www.malwarebytes.org
    • malwarebytes.org
    • download.cnet.com
    • www.download.cnet.com
    • www.bleepingcomputer.com
    • bleepingcomputer.com
    • www.majorgeeks.com
    • majorgeeks.com
    • www.seniorweb.com
    • seniorweb.com
    • www.amazon.com
    • amazon.com
    • www.techspot.com
    • techspot.com
    • filehippo.com
    • www.filehippo.com
    • www.idealsoftware.com
    • idealsoftware.com
    • uptodown.com
    • www.uptodown.com
    • www.mcafee.com
    • mcafee.com
    • home.mcafee.com
    • www.home.mcafee.com
    • www.coolblue.com
    • coolblue.com
    • www.pcmag.com
    • pcmag.com
    • www.sky.com
    • sky.com
    • norton.com
    • www.norton.com
    • www.kieskeurig.com
    • kieskeurig.com
    • internetsecurity.xfinity.com
    • www.internetsecurity.xfinity.com
    • www.symantec.com
    • symantec.com
    • www.campusshop.com
    • campusshop.com
    • www.pandasecurity.com
    • pandasecurity.com
    • www.paradigit.com
    • paradigit.com
    • www.sophos.com
    • sophos.com
    • home.sophos.com
    • www.home.sophos.com
    • sophos.virtualsecurity.com
    • www.sophos.virtualsecurity.com
    • www.gratissoftware.com
    • gratissoftware.com
    • www.seniorweb.com
    • seniorweb.com
    • www.softwareadvice.com
    • softwareadvice.com
    • www.symantec.com
    • symantec.com
    • hostedendpoint.spn.com
    • www.hostedendpoint.spn.com
    • www.g2crowd.com
    • g2crowd.com
    • www.trendmicro.com
    • trendmicro.com
    • www.goedkoopsteantivirus.com
    • goedkoopsteantivirus.com
    • download.cnet.com
    • www.download.cnet.com
    • www.ign.com
    • ign.com
    • www.trusteer.com
    • trusteer.com
    • my.webrootanywhere.com
    • www.my.webrootanywhere.com
    • www.webroot.com
    • webroot.com
    • www.techradar.com
    • techradar.com
    • support.microsoft.com
    • www.support.microsoft.com
    • www.microsoft.com
    • microsoft.com
    • pulse.microsoft.com
    • www.pulse.microsoft.com
    • pcmweb.com
    • www.pcmweb.com
    • www.security.com
    • security.com
    • ccm.net
    • www.ccm.net
    • www.enigmasoftware.com
    • enigmasoftware.com
    • howtoremove.guide
    • www.howtoremove.guide
    • www.2-viruses.com
    • 2-viruses.com
    • www.2-spyware.com
    • 2-spyware.com
    • sensorstechforum.com
    • www.sensorstechforum.com
    • greatis.com
    • www.greatis.com
    • www.pchubs.com
    • pchubs.com
    • www.pcrisk.com
    • pcrisk.com
    • www.malware-board.com
    • malware-board.com
    • pcthreatskiller.com
    • www.pcthreatskiller.com
    • pcfixhelp.net
    • www.pcfixhelp.net
    • stepsforkillingthreats.com
    • www.stepsforkillingthreats.com
    • www.removemalwarevirus.com
    • removemalwarevirus.com
    • spyware-techie.com
    • www.spyware-techie.com
    • anti-spyware-101.com
    • www.anti-spyware-101.com
    • www.removeallvirus.com
    • removeallvirus.com
    • www.pcthreat.com
    • pcthreat.com
    • www.pcinfectionsupport.com
    • pcinfectionsupport.com
    • www.howtouninstallpcmalware.com
    • howtouninstallpcmalware.com
    • computerprotectionpro.com
    • www.computerprotectionpro.com

Step 6

Search and delete these files

[ Learn More ]
There may be some files 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.  
  • %AppDataLocal%\script.ps1

Step 7

Scan your computer with your Trend Micro product to delete files detected as Trojan.Win32.MALREP.THOABAAI. 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 the following Trend Micro Support pages for more information:


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