I never realized that opensource software was a large part of the internet. That seems like a dangerous concept, considering how much our computers/phones are interfaced with the internet.
Actually, with open-source software, you have lots of potential eyes looking at the code. That is how issues like this are found. With closed source, you have to hope the company that is trying to maximize their profit spends a few bucks on people to review their software for issues. Insiders and outside hackers have done similar things to closed-source software (SolarWinds).