The Samsung SM-G930W8 stock ROM is downloadable when you use a Samsung firmware update tool. Though the name doesn’t make it obvious, a firmware update tool will download the firmware files to your desktop. The Samsung firmware update tools download the firmware directly from Samsung’s servers, which is what people generally want so they do not have to put trust in a third-party website. For instance, just because we are telling you about the firmware update tool does not mean you have to trust us; once you use one of the firmware update tools, it’s just grabbing the files directly from Samsung. All you need to do is trust the firmware update tool itself. And they are verified with GitHub or XDA Developers profiles where you can see their files hosted and many people using them.