FireServer changed? What does it mean?

[Quwanterz]

Currently, while I was browsing some Community Tutorials (yes, I sometimes read old topic), I came across this topic:

Preventing Remote Events Logging

This thread is outdated and promotes bad practices, use informationally only. Introduction I feel like Roblox Developers’ biggest problem is when someone discovers a way to trick the system into doing an unwanted action. This is mostly done by logging remote event calls, which is possible with exploits. This thread will in no way secure your Remote calls, and following it blindly will still leave opening spots for exploiters in your game. To ensure your game is safe, you shouldn’t ever trust …

It states in the topic and the post that the FireServer can be… changed??? In which I got confused about it. I tried to research but I can’t tell which keyword I would search. Even though this topic is very old, I still want to know how a function can be changed.

Main question: what does it mean when a function is changed??

Thank you for those who will help me!

[sjr04 (uep)]

That just means exploiters do something like

hookfunction(Instance.new("RemoteEvent").FireServer, function(remote, ...)
    -- something
end)

to replace the :FireServer method with their own so they can see the arguments being passed over for a remote spy.

However they can also just overwrite the __namecall metamethod of the Instance metatable and check when :FireServer specifically is used and log the arguments that way.

[Quwanterz]

I kinda get it, but how does making FireServer variable be (I said be as it is not a foolproof antiexploit) a solution to the problem?

[sjr04 (uep)]

Because the “original” function is cached in a variable. Then the developer constantly checks if remote_event.FireServer == cached_fire_server. If it isn’t then it has been overwritten by an exploiter.

Either way it isn’t a foolproof anti-exploit measure since the exploiter can just kill the anti-cheat script.