Either the Module::CoreList or the command line utility corelist can help you list all the core modules bundled with a given version of Perl.
To know your current running version of Perl : perl -e ‘print $]’
As an example :
fool@localhost:~$ corelist -v 5.014002
Here is a sample of what you can have as information :
The following modules were in perl 5.014002 CORE