RiscV and Spectre
RuscV is an *architecture* - it just happens that exisitng implementations may have simple microarchituectures which may mean they are not suceptible to Spectre but there's nothing in the RiscV architercture to prevent an implementation using the same microarchitectural tricks around speculation that can introduce the ability to use Spectre type attacks as on other architectures. The advantage RiscV may have is that more complicated microarchitectures are being/will be developed in the knowledge of Spectre and so they probably will be designed in a way that tries to eliminatte/minimize the potential for the attacks