If you found software to switch to that is free of security issues, I imagine we would all be interested to know what it is.
You can update both core and modules (similar to plugins for WordPress) using the web interface, which is included with core, or use a command-line utilities like Drush for Drupal 7, or Composer in Drupal 8.
There's lots of very valid reasons to be critical of Drupal, but:
> Drupal is exceptionally bad at this.
I don't think that's accurate.