The thing with "cyber attacks" (oh how I hate that term) is that defense is always much harder. You basically need to "plug all holes" as a defender but the attacker only needs to find one. I'm oversimplifying here a bit as many attacks are basically using chains of exploits to succeed but in general it really is simpler to attack than to defend.

So yes, Russia may succeed there but what does it gain them? Due to this attack/defense asymmetry the west will start doing the same so in the end it's a stupid game where everyone loses or we start physically splitting the internet into smaller nets. That's what will happen if this goes out of hands, everyone loses, just like with this pointless and stupid war.