This week, I learned about tools like Metasploit, which can be used to develop and deploy malware for testing, as well as find vulnerable systems. I had some difficulties installing Metasploit in virtual machines. First, it turns out that turning off Windows defender doesn't really turn it off completely on Windows 10, so installing Metasploit on it was not feasible due to all the detected malware signatures. I had some unrelated problems with upgrading a GNU/Linux virtual machine so that I could install Metasploit, so I wound up opting to install Kali Linux in a virtual machine which now is supposed to include Metasploit, since I had been planning to do so at some point anyway. I found the guides at https://jonathansblog.co.uk/how-to-use-metasploit-to-scan-for-vulnerabilities , https://computingforgeeks.com/how-to-install-metasploit-framework-on-ubuntu-18-04-debian-9/ , and for nmap https://www.cyberciti.biz/faq/install-nmap-debian-ubuntu-server-desktop-system/ ...