How so? Is the activity itself inherently against TOS or laws? It seems to me that by running the competition, ctf365 intends to have users purposefully exploit sandboxed systems.
For example, see 'Prohibited Usage' for Linode: https://www.linode.com/tos.cfm
Unless you're paying for raw bandwidth, you're subject to the ToS of each resource provider along the way.
From their rules:
Don't try to conduct underground activities with your Fortress (system) from our platform in the Real World (e.g. using our platform to spam others, attack other servers on the internet and so on). We don't care who you are, but we do care what you are doing in our home (CTF365 Platform). Please remember that you are our guest and please behave accordingly.
I read this to imply that they will provide the "fortress". So when I say "sandboxed" system, I mean a system provided by ctf365 on their own infrastructure - infrastructure which permission is implicitly granted to attack.
-----------------Network-----------------------------------
my_fortress <- targeted by: competitors_command&control_box
my_command&control_box :targets -> competitors_fortress
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