Today important Cpanel & WHM security updates were pushed out to millions of web servers to address important security issues. Webmasters on their own web hosting must check that their servers update to the latest versions. For shared hosting accounts, your hosting provider should have dealt with the updates.
Cpanel & WHM Updates
Over all these years, I have never got such an email from my Cpanel. It seems this is because this is an important security issue which has been detected and they are keen to push the update to everyone as soon as possible. If you review the Cpanel security issue levels, this issue is classified as Important.
An important rating applies to vulnerabilities that allow system authentication levels to be compromised. These include allowing local users to elevate their privilege levels, unauthenticated remote users to see resources that should require authentication to view, the execution of arbitrary code by remote users, or any local or remote attack that could result in an denial of service.
Auto-Update Cpanel / WHM
Login to your site WHM panel and visit Server Configuration > Update Preferences. Check your server has the latest version of 18.104.22.168 right now.
In most cpanel & WHM installations, the updates settings are configured to update to the latest stable release. You need to check that your server is set to auto-update new software releases, or your server will be prone to hackers. Cpanel would not inform you of minor updates and your server could be stuck with outdated software.
Check in Server Configuration > Update Preferences