Firewall block all local IP adress: 192.168.1.* After updating

[REDACTED]

Hello,

After update my Avast Premier to 17.3.2291 (build 17.3.3443.0) all local IP Adresses 192.168.1.* are blocked. Can not connect to them or to do a PING. I can't connect to my NAS and the rest of my devices.

Please Help. I don't changed anything only update. I have to deactivated the Avast Firewall to work.

OS: Windows 10 64 bits.

Thank so much.

[Pondus]

Any change if you try this and reboot?  >>  https://www.avast.com/faq.php?article=AVKB204#artTitle

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Thanks.

Done but nothing has changed ... The problem continue.

[bobinNaperville]

I'm having same issue and no fix, other than turning all the Shields off, seems to work.  I have updated to build 17.3.3443.0 with no change.

[Alikhan]

Is it the Firewall or the Web Shield which is causing the issue?

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The firewall. I can browse any public URL with no problems. It's only in the local IP 192.168.1.*

I have checked the "allow friendly net in Private" (sorry i don't know the name of this option in english) but not work too.

The range 192.168.1.0 - 192.168.1.255 is in the "Friends" option.

Thanks.

[bobinNaperville]

That seems to depend on the mood Avast is in. Sometimes it's one, then again next time it's both, then next time it's the other.  This was never an issue until the update of two days ago.

[Alikhan]

Could you both run an Avast repair and report back if the issue is resolved?

[bobinNaperville]

NO Change!

[catalan.ua]

Have similar issue. Avast blocks access to my router! I thought that it is a router problem and was thinking to buy a new one! I can login to my router but after few seconds it gets unresponsive.

P.S. Have to disable automatic port scan detection to make it works...

[Alikhan]

I've reported the issue to the Avast devs.

The firewall is not running in public mode, correct?

[Filip Braun]

Hello,

Can you please post in what mode is your Firewall profile (public/private) when you have the issue?
Also knowing your OS helps a lot, since there are differences in Firewall on different OSes.

However the best option to pinpoint the issue would be sending us some debug logs.
Please enable debug logging in Settings > Maintenance > Enable debug logging
And complete Firewall logging in FW component settings > Advanced > Log all blocked packets

After setting this, please reproduce the issue and send us the following logs:
"C:\ProgramData\AVAST Software\Avast\log" folder
"C:\ProgramData\AVAST Software\Avast\fw" folder
"C:\ProgramData\AVAST Software\Avast\Fw.db" file

You can then send them zipped to braun@avast.com

Thank you very much,
Filip

[Filip Braun]

Alternatively, you can check Firewall logs (Firewall page > Firewall logs).
Switch to "Show log for:" Rules
And if you see a message like "Firewall has automatically blocked IP address: <IP_addres> [Port scan detection]"
It means that there was a port scan done from the <IP_address> and Firewall blocked all communications from that address for 30 mins.

Port scan protection is by default turned on, but can be turned off in Firewall settings > Advanced > Port scan detection.

Filip

[REDACTED]

I put my OS in the first message:

FW in Private mode
OS: Windows 10 64 bits.

I will do some bug logs and will send you,braun@avast.com

Thanks

[REDACTED]

I had "And if you see a message like "Firewall has automatically blocked IP address: 192.168.1.- [Port scan detection]" in the rules report.

I turned off in Firewall settings > Advanced > Port scan detection yesterday.

The problem persist.