Cyberpanel cpu 100%

For the past 2 days, around ~14:00, the CPU usage starts to spike almost to 100%, making it nearly impossible for ALL my websites to function properly. I have the latest version of CyberPanel, a Lightspeed server on Contabo with around 10 WordPress websites. The server specifications are adequate: VPS XL NVMe with 10 CPU cores and 60 GB RAM.

I discovered that the issue is limited to a specific WordPress WooCommerce site, likely due to an incompatibility between the latest WooCommerce version and a plugin. My problem and question are: how can I immediately identify the exact cause of this CPU problem? Specifically, it’s clear that it comes from the website, but what exactly is causing it? And most importantly, I find it a major issue that one website can consume all the CPU resources, causing the others to slow down! Is it possible to set a CPU usage limit per page, like we do with memory within WordPress? I feel like I don’t have control over my clients if I don’t know what is consuming memory or CPU. The only command I can use to see some things from the command prompt is htop.

Please help me, I am encountering a major problem with resource management on the CPU. Something is wrong; I don’t know if it is a virus, though I don’t think so. At random times, the CPU usage goes up to 99%-100%, and no site can function properly. I have tried putting Cloudflare in attack mode on the page that spikes the CPU usage, but there was no improvement.

Each time, it recovers simply by putting the site under maintenance. Once the site goes down, the resources return to normal. I noticed that it doesn’t happen only to one site. Yesterday, I put another site under maintenance, and again, the resources returned to normal for a while.

When this happens, I see that almost all sites with processes excessively increase resource usage.

I don’t understand what is wrong; please help me. I have the impression that something is wrong with the Cyber Panel and resource usage.
All my websites run PHP 8.1 and 8.2, and they have the iThemes Security antivirus. I am sure that I haven’t made any significant changes to the websites in recent days that could affect them.