SMB very high data usage

Question

_{Monday, October 22, 2018 3:47 PM}

I'm trying to diagnose high data usage, win 10 upgraded itself to 1803 last week when we wasn't here, I'd left tabs open of YouTube tutorials and when I returned to the PC the videos had started playing automatically. I checked the data usage for the last 28 days and found SMB had used 16.5GB of bandwidth. What does SMB do exactly? I ran a program called shields up! On GRC.com to find my VPN had 3 open ports visible to the internet, ports 80, 443 and one for SSH (I forget the port no.) So is SMB something to worry about or would Edge' data usage be under SMB? I know about the virus that hit the NHS a year or two agao used a vulnerability in SMB. I've asked my VPN provider, who are usually brilliant at replying and I've not heard anulything yet which is worrying.

Darren

All replies (3)

_{Tuesday, October 23, 2018 9:00 AM | 1 vote}

Hi Darren,

Server Message Block (SMB) operates as an application-layer network protoco which mainly used for providing shared access to files, printers, and serial ports and miscellaneous communications between nodes on a network. As SMB can run directly over TCP, port 445, so it is not related with specific broswer. SMB 1.0 is vulnerable to virus, so it was disabled by default on Windows 10. 

Bests, 

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_{Tuesday, October 23, 2018 4:36 PM}

I've run a scan with mbam and it hasn't found anything so fingers crossed I'm still safe. The question is why has SMB used so much data when I was away. I do have shared files on that PC connected to my htpc downstairs, but again I was away from home.

_{Thursday, November 8, 2018 2:07 PM}

Hi Darren，

I am sorry for my late reply.

Please try to use network monitor tool to monitor the bandwidth usage to check if the shared folder was used by your another computer. It would help us to know more details about the background actions.

Bests,

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