First check if you need an update. For that you need to run the following command
perl -v
For updating perl first check the current version of Perl available from cPanel. Check the site
http://layer1.cpanel.net/ and check what the current download link is. I have explained the steps for perl588
==> cd /usr/src/
==> wget
http://layer1.cpanel.net/perl588installer.tar.gz==> tar xvzpf perl588installer.tar.gz
==> cd perl588installer
==> ./install
Once the process completes cPanel need an update, so run upcp