my antivirus (Avast Internet Security) it´s detecting UNDERTALE.EXE as virus

[x²]

why i go play undertale my antivirus (Avast Internet Security) is detecting UNDERTALE.exxe as virus he is showinng:
blocked possible malicius pogram
process:UNDERTALE.exe
Possible malicious program: WIN32[pup]
It can be harmful to your computer, or unwanted
its a false positive?

[Mother of Exiles]

//Considering how many people play it, what do you think?

[MythlyInari]

Undertale is not a virus. If it were, it would have been noticed since September 15th of last year. It's fine. It's a false positive.