On a web site using xpanel control panel (free hosting script created with perl), i get error

[Sun Jul 16 03:27:04.202640 2017] [cgi:error] [pid 9711] [client 112.133.248.10:5675] AH01215: Can't locate CGI.pm in @INC (@INC contains: /usr/local/xpanel/ /usr/local/lib64/perl5 /usr/local/share/perl5 /usr/lib64/perl5/vendor_perl /usr/share/perl5/vendor_perl /usr/lib64/perl5 /usr/share/perl5 .) at /usr/local/xpanel/insert/category1.cgi line 24.
[Sun Jul 16 03:27:04.202705 2017] [cgi:error] [pid 9711] [client 112.133.248.10:5675] AH01215: BEGIN failed--compilation aborted at /usr/local/xpanel/insert/category1.cgi line 24.
[Sun Jul 16 03:27:04.202783 2017] [cgi:error] [pid 9711] [client 112.133.248.10:5675] End of script output before headers: category1.cgi

This is because perl-CGI module was missing on the server.

On CentOS 7 server, you can install it with command

yum install perl-CGI