Yesterday, Google Search Console sent batches of alerts and notifications to webmasters operating popular CMS (content management systems) such as Wordpress and Joomla to update their version of their CMS if they were out of date.
Most people are talking about the Wordpress notification, but it went to many flavors of CMSs including Wordpress, Joomla and others.
The email alert reads for Wordpress:
Google has detected that your site is currently running Wordpress 4.7.0 or 4.7.1, an older version of Wordpress. Outdated or unpatched software can be vulnerable to hacking and malware exploits that harm potential visitors to your site. Therefore, we suggest you update the software on your site as soon as possible.
The email alert reads for Joomla:
Google has detected that your site is currently running Joomla 1.5, an older version of Joomla. Outdated or unpatched software can be vulnerable to hacking and malware exploits that harm potential visitors to your site. Therefore, we suggest you update the software on your site as soon as possible.
Obviously the version numbers can change depending on which version you are running.
The Google Webmaster Help forums and WebmasterWorld forums are on fire with tons of posts about these notices.
What should you do? Upgrade.
Forum discussion at Google Webmaster Help and WebmasterWorld.
Update: Some are claiming that the alerts to some webmasters are wrong and that their Wordpress sites are updated. It might just be a timing and delay issue.