Hello,
Avast Antivirus does not configure any VPN. With Catalina, Apple has introduced Network Extension framework (
https://developer.apple.com/documentation/networkextension?language=objc) for intercepting network traffic (which our Web Shield and Mail Shield need to do) instead of the old way (via Kernel Extension). This framework was AFAIK originally used on MacOS only to implement VPN, however on iOS it has also already contained the network traffic interception. This functionality was ported and expanded to MacOS in Catalina, although in an immature state. With Big Sur, Apple has discontinued kernel extensions, so we had to switch to this new technology.
Unfortunately despite the fact we are not using the VPN part of Network Extension (our system extension which uses Transparent Proxy for our Pro and Free version and additionally Dns Proxy for our Pro version), the Transparent Proxy functionality, used for scanning network connections, shows as VPN in Networks in System Preferences. This is probably because parts of the functionality used for managing Transparent Proxy are also used for managing VPN; we have already reported one other case where "VPN" term was erroneously used in messaging and Apple has renamed it to more appropriate term. We have already reported this naming issue, however due to the fact that this is not only a case of name change, but there are multiple graphical elements shown, it is hard to say when/if this will ever be changed by Apple.
So please rest assured, unless you buy our VPN product, there is no VPN active. However as long as you have Web Shield or Email Shield active, there will be this record in Network (and since manually deleting it stops these shields from working, Avast keeps recreating it).
As an aside, it seems that there is some bug or glitch when Transparent Proxy starts, as the start sometimes causes multiple records (with yellow dot, in Not Connected state) to be created. This has already been reported to Apple and hopefully also be addressed soon.
Please note, that these "issues" do not impact the underlying functionality, despite the fact that they are annoying and confusing. We apologise for any confusion we are causing.
Kind regards,
Ondrej Kolacek