Currently hackers can easily hack the websites made with the wordpress and you can take the below precautions to secure the wordpress websites and also can improve its performance with the help of below things ”
1. update WordPress >> If you’re not using the latest version of WordPress update now. Make sure you backup your site first!
2. Update your WordPress Plugins >> Updating your WordPress plugins to the latest versions can often reduce high CPU usage. If you’re running an old version take a moment to update
now. Also Whilst it’s very cool to be on the cutting-edge, only use stable versions of plugins. Sometimes early release versions (also known as alpha or beta) can have bugs in the code which can cause CPU spikes.
3. install a caching plugin >> Caching plugins such as WP Super Cache and W3 Total Cache can dramatically reduce CPU load by caching static copies of your pages on your web space. Static files use less CPU and memory. Keeping you within your shared-hosting limits.
4. Only use plugins you really need >> Do you really need that plugin that constantly checks for broken links? – The more WordPress plugins you have installed, the longer your site will take to load. Deactivate and delete any plugin that you don’t need. Aim for just a handful of plugins. This will speed up your site and keep your visitors happy.
5. Avoid using resource-hungry plugins >> The more complex WordPress Plugins such as WP e-Commerce and NextGen Gallery require lots of CPU and memory and are best suited to VPS, or dedicated servers. If you try running them on a shared-host you risk your site being suspended due to high-CPU loads.
6. Ask the WordPress Community for help >> Try searching WordPress Forums for answers. If there’s a known problem with a plugin there’s a good chance someone will have provided a solution.
7. Disable WP-Cron >> WP-Cron manages all the scheduled events in your WordPress site. WP-Cron is a very common cause of high CPU loads. Disabling WP-Cron can drastically reduce CPU-load and prevent the chances your account is suspended due to exceeding your resources.