Suspect Avast AV to crash my home ISP router - "SSH user logged out" message

Avast Free Antivirus / Premium Security
1

Hi, I am using the latest Avast Free Antivirus software with latest data base, on windows 10.

I have a home network with 10-15 IP addresses (tablets, smart phones, laptops, PCs, printer etc.).
I have 2 PCs with Avast Anti Virus on them.

When ever any one of these 2 laptops connects to the network, it crashes my ISP home router which then reboots. This is really annoying because I am working in home office and I am kicked out of the Teams call I am on until my Internet connection restarts.

Looking at the logs, a few seconds before the router crash, I see this: “SSH user logged out”

This is really scaring me because I did not do any port forwarding on port 22, so SSH should not be possible from the outside. I hope that I have not been hacked.

I suspect Avast AV software on those laptops to be the origin of this problem. Since this morning I dis-installed all Avast Antivirus software from all my PCs. I have not see any more crashes of my home router, and would need a few more days of noticing no crash before I can consider this fixed.

My question to Avast is then: could Avast AV be generating behavior explaning these “SSH user logged out” messages and crash of my Home ISP router?

2
  • Which version/build of Avast Free…?
  • OS…? (32/64 Bit…? - which Build…?)
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?
3

  • Which version/build of Avast Free…? The latest one, I updated it this morning and even so my router crashed after that.

  • OS…? (32/64 Bit…? - which Build…?) Windows 10 64 bits with the latest patches (build 2004 for 1 PC and not yet installed 2004 on the other PC)

  • Other security related software installed…? Bitdefender anti ransomware on one of the PCs

  • Which AV(s) did you use before Avast…? None. But now I will use no AV at all if it crashes my router.

Can you respond to my question:
Could Avast AV be generating behavior explaning these “SSH user logged out” messages and crash of my Home ISP router?

4

Follow instructions: https://support.avast.com/article/33/ and post the File-ID and/or name of the Support-File here afterwards.

5

Hi you don’t understand, I remove the Avast AV all together with no intention to re-install unless the problem re-occurs even without the AV.

My question is generic: My question to Avast is then: could Avast AV be generating behavior explaning these “SSH user logged out” messages and crash of my Home ISP router?

Sorry no time for troubleshooting.

6

I doubt anyone can answer that without any logs.

7

Well in this case, if I do not have any more crash in the next 2 weeks with the AV uninstalled , I will attribute the root cause of the home router crash to the AV. An never install Avast again on my network.

You should investigate in your customer service if you had had similar complaints, and understand the way the software can generate such events without looking at any logs.

8

NP, do as you like…

9

You’re in luck. I had not completely removed the software yet.
File name: 20200903_1824_OJZVU_3963314118.zip

Note that the crash on my Network with the message appeared on 3 September at 08:40:02

See my router:

https://i.ibb.co/ZzSYLhg/NUMERICABLE.jpg

10

Hi. Any update? I just launched Windows and a few seconds later the same happened on my router, it was forced to reboot. Then I pause Avast and no more problems.

I am putting the logs of the crash that happened at about 16:47 today.I am also sending to the support teamthe new log file from Avast.

20200909_1459_XEG48_3963314118

09/09/2020 à 16:47:00 MDD message timeout;CM-MAC=40:65:a3:e1:73:ba;CMTS-MAC=00:56:2b:76:4a:43;CM-QOS=1.1;CM-VER=3.0;

09/09/2020 à 16:46:58 Unicast DSID PSN startup error

09/09/2020 à 16:46:45 SSH user logged out.

11

Hi, the issues is reproduced constistently everytime I switch my PC on.

I have already sent 3 Avast support files, with the log from my router just before each crash.

This should be ample information for you to identify the root cause.

The latest Avast support file is 20200912_1338_6EM1Y_3963314118

12

Hi, some fixes have been released during the week. Are you running build 20.7.5568.595…!?

13

Hi, I am on 20.7.2425 - version 20.7.5568.595

I updated on 1st September, so I am not sure what you mean by some changes last week?

14

Is your router software updated …

15

Hi my router is controled by my ISP, I can’t update or anything myself. My router is a few months old, so should be fairly recent.

16

I sent all the Avast log files and my router log files, someone from Avast should look at it, to try to understand the root cause.

17

I have tried to draw Avast attention to this topic.

18

The initial buld was 20.7.5568.590