If you are sure the chips are not getting too hot, then the issue could be a bad thermal sensor.
Now if you are judging it’s “heat” from outside the unit, it may actually be having an issue. A lot of PS4’s have had fans that fail or improper thermal paste. The fan is, by far, the cheapest thing to replace. The thermal sensors are built into the motherboard.
About Booters: Booters find the WAN IP address of your network and flood it with garbage data. Essentially, it is a Denial of Service attack. This alone does not change anything inside your PS4, so the current issue is unrelated and the timing coincidental.
To protect your IP address, you could use a VPN service. Once they have your real-world IP, there is not much you can do to stop the DoS attack. If you have a dynamic IP address with your ISP, you could try leaving your modem offline for several hours to see if it gets a different IP address when powered back on. Also, you can ask your ISP to assign a new IP address, just explain what is happening.