Most software bugs do not result blocking internet access or any virus like behavior, they may crash your game, they may not allow you to do particular thing in your application you are running. They don't generally send out key log information, allow a remote attacker to gain to your computer (sometimes they do but usually not), make your computer part of a DOS attach.
By the original definition
Any software is malware when it does something other than the user intended.
all software bugs are malware, because they probably do what the at least one user doesn't want. In fact, this definition is so broad that, even an application that has no bugs is probably defined as malware, if it has a single feature that the any user doesn't like, no matter how innocuous, e.g. uses a font that the user doesn't like.