Even if it sounds dummy, ALWAYS CHECK YOUR PLUGINS!
Nowadays, the WP community has launched a lot of useful and not so useful plugins. Many of them have holes and can cause issues on your websites.
Usually, that happens when using most popular plugins. For example, a very popular and world-famous GDPR plugin had a hole in its system and was sharing data or creating another user by itself or remotely. And that’s just a tiny example of such issues!
Also, some newbies are making a lot of mistakes during plugin development because of not reading WP Codex where everything is accurately described.
Please be attentive and careful!
WP developer of Bineks