Network attack on Windows PC?

[PsychoPendos]

Last night I left my PC on for a couple hours and when I returned, it was under such load, that even mouse movement displayed with latency about 30-40 seconds. It struggled to open task manager, but I noticed, that hard drive LED was constantly showing load on my drive. First thought, that I had, was to remove Ethernet cable. Once I did it, everything disappeared and task manager opened. And the last thing it showed after load was 99% CPU and memory load. And I certain, that my SSD was under load too. 
Who know what was it and should I be concerned about anything?

 

PC specs:

Asus A88XM-E with latest BIOS
A10 7870K

8GB DDR3 1866MHz x2

MSI R9 380 4GB

512GB SanDisk SSD

500 WD Blue HDD

650W PCU

[Votivee]

Quote

Location: Moscow, Russia

 

29 minutes ago, PsychoPendos said:

should I be concerned about anything?

You should be concerned about everything. /s

 

Do you have antivirus? Sometimes antivirus programs can do some pretty rigorous idle scans.

[PsychoPendos]

15 hours ago, Votivee said:

Do you have antivirus?

Only default Windows Defender. But for the last 4 years on 6 Windows 10 PCs I never saw such load on a system. Basically, for all of the 12 years that I consciously use PCs, I never saw something like that before. Even when it was caused by a program and/or synthetic hardware test. 

And considering the fact that it was tied up to Ethernet connection, I assumed it was an Internet based attack. But I'm not an expert in this topic

[ch7474]

Connect it again, see what process is causing it. Log connections w/ wireshark or maybe find an easier program, see what connections are being made. And see exactly what components are being taxed. Sounds more like a bug related to your nic. But there isn't enough info given. Could be a miner or the like. 

[PsychoPendos]

On 7/27/2019 at 1:01 PM, ch7474 said:

Connect it again, see what process is causing it. Log connections w/ wireshark or maybe find an easier program, see what connections are being made. And see exactly what components are being taxed. Sounds more like a bug related to your nic. But there isn't enough info given. Could be a miner or the like. 

I connected cable back in a minute and it was a couple of days since, nothing like that appeared again so far. After that load I checked my PC with Malwarebytes and CureIt, there is nothing. So I'm confident that it wasn't something on my PC. 

And yeah, I know there's not much information about what happened, because it happened only once and I don't know how to check what it was

[ch7474]

On 7/29/2019 at 2:41 AM, PsychoPendos said:

I connected cable back in a minute and it was a couple of days since, nothing like that appeared again so far. After that load I checked my PC with Malwarebytes and CureIt, there is nothing. So I'm confident that it wasn't something on my PC. 

And yeah, I know there's not much information about what happened, because it happened only once and I don't know how to check what it was

Nice, if you want to be careful you can do a reset. At this point, I have everything setup, so I can easily reset. If anything sketchy comes up. Troubleshooting takes a long time.