Editing Portal:SaaS and Web Development (section)

=== Perl web security lessons ===

Perl’s early web dominance also taught many security lessons. CGI scripts made it easy for ordinary users to put code on the Internet. That power came with risks.

Common Perl CGI security concerns included:

* trusting form input;
* failing to escape HTML output;
* command injection through shell calls;
* unsafe file uploads;
* world-writable files;
* weak permissions;
* exposing configuration files;
* sending spam through insecure form-mail scripts;
* using outdated modules;
* mishandling cookies or sessions;
* leaking database credentials.

Perl responded with practices such as taint mode, input validation, strict and warnings, better templating, parameter handling, mature CPAN modules, and more structured frameworks. The Perl community learned that web programming was not only about generating pages. It was also about trust boundaries, escaping, permissions, and deployment.