(quoted from post at 08:46:45 01/11/20) > So, is it just Firefox browser that is vulnerable? I switched to Chrome a few years ago, and I did not know about the Java threat. I always disregarded the updates Java offered because of slowdowns I had experienced on downloads. But when I switched over to Windows 10 the other day, The Java update window came up and I downloaded it. I thought Java was something necessary for the OS. Am I wrong?
Since the flaw is in IonMonkey, the Java Script just-in-time compiler specific to Firefox, the vulnerability is in Firefox only.
Java is, in general, not required by the Windows operating system. However, there are a number of websites and platform-independent applications that do require Java, so if you were to uninstall it you would likely run into problems.
Just to clarify, Java is a general-purpose programming language that allows a program to be compiled once, then run on multiple platforms such as Windows, Linux or macOS. ("Native" programs, on the other hand, have to be compiled for each platform. These would be written in languages other than Java, such as C++) In order to execute a compiled Java program, a computer must have the Java Run-Time Environment (RTE) installed; that's the "Java" that your update was for.
Java Script is a scripting language that runs inside a browser and is used by many websites to automate various functions. Java Script is tied to the browser and is unaffected by updates to the Java RTE.