There are certain risks with it. In my advocacy I always try to push for uni-directional paths on each side of the road because of that. But honestly the safety concerns are minimal when compared to no bike path at all, or just an on-road bike lane.

The biggest danger is people coming out of driveways or side streets failing to look both ways. It's extra useful, therefore, to use wombat crossings across side streets, and to put small, sharp speed bumps beside the path on driveways. Here's an example near me:

(Just ignore the stencilled white pedestrian indicator on the bicycle-path green-painted path. That's a whole separate problem of poor inconsistent design...Especially since there's an unpainted concrete footpath right next to it.)

But even if you don't do that, it's pretty damn good. It takes away all fear for 90% of the length, and just requires attentiveness from the cyclist when they approach intersections. Less than perfect, but still quite good.