The Wild Wild West of the Internet is a borderless place!
Who has Jurisdiction on the internet?
Who has Jurisdiction where this attack on . . . happened
If we are thinking about Who will come riding in to Save the Damsel in Distress, NO ONE. The traditional Law Enforcement agency works in physical area. If you are on the bank of a river, for instance, you may be asked, "Which bank of the River?". "Our office only handles the right bank."
On the internet, there is no physical area.
There is a physical area where the entrance to the internet exists. But in a second that entrance is gone. SO is the phsycal area where the entrance exists, even for the second, the jurisdiction we are looking for?
There is a physical area where the exit from the internet exists. But in a second that exit is gone. So is the phsycal area where the exit exists, even for the second, the jurisdiction we are looking for?
If the attack is from a server, YES!
If the attack is from a person, NO!
If the attack is on a server, YES!
If the attack is on a person, NO!

When a traditional Law Enforcement Agency is asked,
What are you doing about this attack on . . .?
The reply is
We Are Doing All We Can!
because they can do Nothing!

The Wild Wild West of the Internet is lawless!