What is Compiler Access and does this need to be activated?
Many common exploits require a working C compiler on the system.
Typically you will only need the root user to have access to the compiler and this wouldn't need to be activated for all users.
However, in some instances, you might need to give users access to the compiler. If this is needed it can be done within WHM » Security Center » Compiler Access.
This interface allows you to allow or deny compiler access to unprivileged users. You can also choose to allow some users to use the compilers while they remain disabled by default.
The following documentation explains this in greater detail: Compiler Access