What most people think of as Linus is really GNU/Linux, and while I don't think the distinction usually needs to be made, it's actually important in this case because it makes it obvious there is no one "thing" to infect and change. Linux is a commodity, and open, and we're in no threat of major problems like that than we are of someone jacking up the price on ibuprofen. The solution is the same in both cases, someone else will offer a better alternative because there's nothing forcing you to use the bad offering.