How to Manually Upgrade Drupal Core on Ubuntu

A severe remote code execution vulnerability has been found in Drupal CMS. Users are advised to manually upgrade their Drupal from the command line console or via the hosting platform, as upgrading from the admin dashboard is not possible. The upgrade process includes putting the site in maintenance mode, deleting core files, restoring them with the latest versions, updating the core database tables, and checking everything is working fine before exiting maintenance mode.

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