Eric Mann

DGXPCO (Digital Guarantees for eXplicitly Permitted Core Operations) is a proof-of-concept cryptographic signature verification utility for WordPress software updates. The plugin will source manual (offline) signatures for WordPress core updates and prevent the application from updating unless the contents of the update payload are verified with a remote signature.
This provides a second source of truth for the integrity of WordPress updates beyond the MD5 content hash supplied in the header from the WordPress update server. If that server were ever breached, it’s unlikely the server hosting the signatures of the files was also breached. If the signatures ever fail to validate, you can know your site was protected from an attack.

DGXPCO

Jon Cave

If you don’t check your admin panel on your WordPress install very often (maybe because you prefer to use remote publishing) or you want to make sure 
that your clients’ WordPress installations are updated, then this is the plugin for you. You don’t have to login to your admin panel regularly, 
suscribe to an RSS feed, or do anything apart from installing this plugin to be notified when an update to WordPress is released.
All you have to do is install Update Notifier and forget it until you receive an email telling you to update.
To change Update Notifier’s options, go to Update Notifier under the main Settings menu. From there you can add a secondary email address 
which will also receive update notifications and you can activate update notifications for themes and plugins.

Update Notifier

Sends email notifications if a new version of WordPress available. Notifications about updates for plugins and themes can also be sent.

DGXPCO vs Update Notifier