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Seems my PC is infected. Possibly bitcoin miner or similar virus.

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So, recently, like a month ago I noticed my PC getting slower, at times quite slower, even though I'm not really doing anything on it, like I'd notice my cursor lagging like I have 2 big video games running in the background. I also noticed when I open Task Manager it's always at like 50% and then it drops fast down to 5-10%. The task manager alone wouldn't really be a proof but this getting slower thing definitely is I think, especially if PC is on for longer periods. Like last night, I left it on, and today I could barely open any page or any program, they just get non responsive immediatelly. I had to restart PC to actually get it to do anything. This happened before as well (since this started), every time I leave it on for longer periods it gets slower and slower, and that never hapenned before.

So I did a little googling and came up with this forum. I'm no expert on the matter, but according to some threads I read I might have this bitcoin miner thing that hides when you open Task Manager and when it's not opened it uses your computer resources. I could be wrong though, since I don't really know about these things. I did what you guys advised in those threads with the Malwarebytes, Adwcleaner and a Farbar Recovery Scan Tool, and got some detections which I quaranteened, but the problem, it seems, still persists, so I decided to open a thread for further assistance. Also, I did a scan with NOD32 that I use, and it showed no detections. Attaching logs below.

Addition.txt AdwCleaner[C00].txt AdwCleaner[S00].txt FRST.txt malwarebytes log.txt malwarebytes log2.txt

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Hello mladenq and welcome to Malwarebytes,

Continue please:

Please download the attached fixlist.txt file and save it to the Desktop or location where you ran FRST from.

NOTE. It's important that both files, FRST or FRST64, and fixlist.txt are in the same location or the fix will not work.

NOTICE: This script was written specifically for this user, for use on this particular machine. Running this on another machine may cause damage to your operating system that cannot be undone.

Run FRST or FRST64 and press the Fix button just once and wait.
If the tool needs a restart please make sure you let the system restart normally and let the tool complete its run after restart.
The tool will make a log on the Desktop (Fixlog.txt) or wherever you ran FRST from. Please attach or post it to your next reply.

Note: If the tool warned you about an outdated version please download and run the updated version.

NOTE-1: This fix will run a scan to check that all Microsoft operating system files are valid and not corrupt and attempt to correct any invalid files. It will also run a disk check on the restart to ensure disk integrity. Depending on the speed of your computer this fix may take 30 minutes or more.

NOTE-2: As part of this fix all temporary files will be removed. If you have any open web pages that have not been bookmarked please make sure you bookmark them now as all open applications will be automatically closed. Also, make sure you know the passwords for all websites as cookies will also be removed.

The following directories are emptied:
  • Windows Temp
  • Users Temp folders
  • Edge, IE, FF, Chrome and Opera caches, HTML5 storages, Cookies and History
  • Recently opened files cache
  • Flash Player cache
  • Java cache
  • Steam HTML cache
  • Explorer thumbnail and icon cache
  • BITS transfer queue (qmgr*.dat files)
  • Recycle Bin

Important: items are permanently deleted. They are not moved to quarantine. If you have any questions or concerns please ask before running this fix.

The system will be rebooted after the fix has run.


Download Sophos Free Virus Removal Tool and save it to your desktop.

If your security alerts to this scan either accept the alert or turn off your security to allow Sophos to run and complete.....

Please Do Not use your PC whilst the scan is in progress.... This scan is very thorough so may take several hours...
  • Double click the icon and select Run
  • Click Next
  • Select I accept the terms in this license agreement, then click Next twice
  • Click Install
  • Click Finish to launch the program
  • Once the virus database has been updated click Start Scanning
  • If any threats are found click Details, then View log file... (bottom left hand corner)
  • Copy and paste the results in your reply
  • Close the Notepad document, close the Threat Details screen, then click Start cleanup
  • Click Exit to close the program
  • If no threats were found please confirm that result....

The Virus Removal Tool scans the following areas of your computer:
  • Memory, including system memory on 32-bit (x86) versions of Windows
  • The Windows registry
  • All local hard drives, fixed and removable
  • Mapped network drives are not scanned.

Note: If threats are found in the computer memory, the scan stops. This is because further scanning could enable the threat to spread. You will be asked to click Start Cleanup to remove the threats before continuing the scan.

Saved logs are found here: C:\ProgramData\Sophos\Sophos Virus Removal Tool\Logs

Let me see those logs in your reply, also tell me if there are any remaining issues or concerns...

Thank you,




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Hey kevinf80!

So to summarise, I download the attached fixlist.txt file and save it to the Desktop (I ran FRST from there the first time), then I run FRST and click FIX, which will delete all of my temporary files (which are not really important) and then my PC will reboot. Then I download Sophos Free Virus Removal Tool and run it. When that scan finds a threat it will stop, and I should then copy that log and after that I click Start Cleanup so the threat is removed and scan is continued? Finally I upload the logs here?

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Ok, did both, attaching logs. Sophos had one detection.

So I guess, my questions now are:

1) Was I right to suspect viruses causing PC to go slow over time? That is, could these things that Malwarebytes, Adw and Sophos found and removed be responsible for that? Also for CPU getting higher until Task Manager is opened.

2) Am I in the clear now? 'Cause it still seems that CPU is up to 20-30% at least when I open Task Manager, then it goes down to like 5% immediatelly.  Here's a couple of examples, https://i.gyazo.com/a1ea9d28b3d3d74e62498811d2eae1e6.mp4https://i.gyazo.com/7f170104b8c0ec1cbbfa11004ef4c516.mp4https://i.gyazo.com/8bd3fae04223563f05ac945f5f986e9d.mp4. In them it's like 40-50% when I open TM then it goes down to 20%, but I'm assuming that's because of the Gyazo as it's displayed in TM, however when I just open it normally without Gyazo, it's like up to 30% then it goes down to 0-5%. I remember before, this would be like 5-10% when I open it, so I'm guessing it's not normal behaviour?

Fixlog.txt sophos log.txt

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Hello mladenq,

Run the following please:

user posted imageScan with Autoruns

Please download Sysinternals Autoruns from the following link: https://live.sysinternals.com/autoruns.exe save it to your desktop.

Note: If using Windows Vista, Windows 7, Windows 8/8.1 or Windows 10 then you also need to do the following:
  • Right-click on Autoruns.exe and select Properties
  • Click on the Compatibility tab
  • Under Privilege Level check the box next to Run this program as an administrator
  • Click on Apply then click OK
  • Double-click Autoruns.exe to run it.
  • Once it starts, please press the Esc key on your keyboard.
  • Now that scanning is stopped, click on the Options button at the top of the program and verify that the following are checked, if they are unchecked, check them:

    Hide empty locations
    Hide Windows entries

  • Click on the Options button at the top of the program and select Scan Options... then in the Autoruns Scan Options dialog enable/check the following two options:

    Verify code signatures
    Check VirusTotal.com

  • Once that's done click the Rescan button at the bottom of the Autoruns Scan Options dialog and this will start the scan again, this time let it finish.
  • When it's finished and says Ready. on the lower left of the program window, please click on the File button at the top of the program and select Save and save the file to your desktop and close Autoruns.
  • Right click on the file on your desktop that you just saved and hover your mouse over Send To and select Compressed (zipped) Folder
  • Attach the ZIP folder you just created to your next reply..

Thank you,


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We need to upload a file to Jotti

1. Go here: http://virusscan.jotti.org/ to get to Jotti's site. Accept the cookie option.

2. Use the Browse button to locate the following file on your system:

c:\program files (x86)\skillbrains\updater\updater.exe

3. Once you have located the file, click SUBMIT and the content of the file will be uploaded by the site and analysed.

4. Please provide me with the results of the analysis.
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Yes it was flagged by 4 scanners at virustotal showing in the autoruns log... Can you uninstall Skillbrains and see what effect that has...

Download GeekUninstaller from here: http://www.geekuninstaller.com/download (Choose free version) Save Geek.zip to your Desktop. (Visit the Home page at that link for necessary information)

Extract Geek Uninstaller and save to your Desktop. There is no need to install, the executable is portable and can also be run from a USB if required.

Run the tool, the main GUI will populate with installed programs list,

Left click on Skillbrains to highlight that entry.

Select Action from the Menu bar, then Uninstall from there follow the prompts.

If Uninstall fails open the "Action" menu one more time and use "Force Removal" option...
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Yes it aint malicious per se, but it did seem to be busy in the background, hence I wanted to remove it. Did you install that software, do you really need it..? Having its uninstaller tucked away does seem suspicious..


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If the cpu issue is still happening maybe worthwhile trying to find out why. It is not uncommon for a high CPU reading to drop away when Task Manager is opened, there have been many threads with that problem here at Malwarebytes, also several moderators have also made a reference to that anomility...

Run your system in "Clean Boot" mode see if that makes any difference:

Set windows up for "Clean Boot" mode, full instructions here: https://support.microsoft.com/en-gb/kb/929135

Basically all none MS services are disabled, see how your system runs in that mode. Obviously 3rd party services that affect security or internet connection can be left active.

If clean boot makes your system faster and more responsive it is now a process of elimination to find which non MS service(s) was affecting your system...

Go through the process again, this time with all MS services hidden again enable the top half of non MS services, re-boot and see how your system responds, if still ok the top half can be left enabled.

Repeat again, enable so many of the bottom half then re-boot. Continue until you locate the problem service(s). A process of elimination, a bit long winded but worth the effort. Let me know the outcome...


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To be honest, I'm not sure if I have the time for that these days, but I might have to resort to that if the PC slowdown comes back. It worked normally yesterday, so I figure we might've removed the thing that was messing with it in one of those earlier removal processes?

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Hello mladenq,

If you are ok to close we can clean up, if your problem returns you can PM me or any other Moderator to have your thread reopened.....

Uninstall the following programs:

Sophos AV


Also delete this folder if still present: C:\ProgramData\Sophos


Right click on FRST here: C:\Users\mladenq\Desktop\FRST64.exe and rename uninstall.exe when complete right click on uninstall.exe and select "Run as Administrator"

If you do not see the .exe appended that is because file extensions are hidden, in that case just rename FRST64 to uninstall

That action will remove FRST and all created files and folders...


Remove all System Restore Points: https://www.tenforums.com/tutorials/33593-delete-system-restore-points-windows-10-a.html#option2

Create clean fresh Restore Point: http://www.thewindowsclub.com/create-system-restore-point

Run Windows Disk Clean Up Utility - https://neosmart.net/wiki/disk-cleanup/

Download and use a Password Management application. https://www.windowscentral.com/best-password-manager-windows

Malwarebytes Browser Guard (Free) for Firefox: https://addons.mozilla.org/en-GB/firefox/addon/malwarebytes/

Malwarebytes Browser Guard (Free) for Chrome: https://chrome.google.com/webstore/detail/malwarebytes-browser-guar/ihcjicgdanjaechkgeegckofjjedodee

From there you should be good to go...


Read the following links to fully understand PC Security and Best Practices, you may find them useful....

Answers to Common Security Questions and best Practices

Do I need a Registry Cleaner?

Take care and surf safe

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