Tmp Folder On My Server is Filling Up Very Quickly

Hi, /tmp folder on my server is filling up very quickly. Every day I clean the tmp folder with cronjob.But during the day, it quickly fills up again. what can i do about it?

When I checked it with netstat, I saw that there were over 150 connections on a specific ip and i blocked ip.

My /tmp Folder Size 1.6G.

Can anyone help me with this?

My System :

Ubuntu 18.04 LTS CyberPanel.