I didn't build our site but I know my coworkers used a free template for it which had quickstart installer and also has not received any updates (wordpress itself and its plugins) for several months and I think maybe it's because of that.
there were some .php files in that folder contain the...
the tasks which lsphp (v 5.6.33) creates in /tmp with name of php + random-hash, take too much CPU of my server.
they also have a long uptime, for example, 16h (and still remains until I kill them).
when I kill one of them, the others will be gone too and cpu usage falls down to normal.