How similar or different is Tantric Buddhism from Vijnana Bhairava of Kashmir Shaivism?

Tantra exists in certain traditions of Buddhism (I guess mostly in Tibetan and certain Theravada schools as well). It also exists in Kashmir Shaivism, as explained in the Vijnana Bhairava. Can someone please help me understand how the schools Buddhism and Kashmir Shaivism differ (and are similar) in their approaches as well as goals for Tantric practices.