It depends on the context/usage. It's not usually used as 'cute', but it can be used as such. Angry mother to her child: Be quite and stop acting silly or you'll be grounded! Friend to friend, speaking casually: I thought the play was kind of silly, to be honest... Shy girl or guy that wants to say cute, but can't: You're so silly, you know that? d:

I have never seen silly being used to mean cute. By definition it means someone or something is being foolish. You are correct that it tends to be a lighter term, when someone is lacking common sense. In a more informal was silly could be used to show affection. Someone might say a baby is being silly when they are being foolish in a cute way. Or another way might be to say "you are being silly" to mean you are funny, or not taking some thing seriously, or goofing off.

no, "silly" doesn't mean "cute"

As you said, "silly" is lighter than "stupid" and kind of suggests "it's alright, no big deal". But I doubt any respectable adult uses it to mean "cute" or for any positive connotation.

Silly can be used negatively and positively. I guess silly can mean cute sometimes