CPU 100% usage caused by woocommerce

The error message you provided indicates that there is a problem with a plugin called WooCommerce. Specifically, the error is occurring in a file called CoreMenu.php within the plugin. The error message states that there is an issue with trying to access an array offset on a value that is null.

Here are a few things you can try to troubleshoot the issue:

1. Check for plugin conflicts: Deactivate all other plugins to see if the issue is resolved. If it is, reactivate them one by one to identify the conflicting plugin.
2. Check for theme conflicts: Switch to a default WordPress theme (e.g. Twenty Twenty-One) to see if the issue is resolved. If it is, there may be a conflict with your current theme.
3. Check for outdated plugin or theme: Make sure that the WooCommerce plugin and your theme are up to date.
4. Check for server resources: Make sure that your server has enough resources to handle the traffic and usage.
5. Check for any script running in background: Check for any script or cron job that might be running in background that is causing the high CPU usage.
6. Check for any security issues: run a scan and check for any security vulnerabilities that may be causing the issue.

It’s recommended to check the above points, and if you are still unable to resolve the problem, it may be necessary to consult with a developer or a system administrator with more experience in troubleshooting server and plugin issues. Also, you can contact Cloudways support team and provide them with the error report, they can help you to further investigate the issue.