What is the best adhesive to use with unpainted cement walls?

I want to adhere cardboard to unpainted cinder block walls. So far i have tried tape and sticky tack, but to no avail. Anyone have other ideas?What is the best adhesive to use with unpainted cement walls?
Try caulk. That'll stick almost anything to almost anything else. What is the best adhesive to use with unpainted cement walls?
Use industrial strength double sided mounting tape (not picture mounting tape). It's used to mount things to exterior of buildings, etc. It has a red pealing back and is not recommended on some walls because it can take the plaster right off. This type of tape will adhere to a clean surface. Make sure the cinder block is free from loose particles (a wire brush to get off the particles), dust and is dry. Use a good amount of mounting tape and press firmly for at least 30 seconds to a minute before removing the red backing. Then take off the backing and adhere the cardboard right to it.
Cinder block is so porous that no glue will hold for long. Tape will be useless as the surface area that it covers is less than 1/2 the area that will actually touch the block and the sheer weight of tape will cause it to fail. I would use drywall compound. Apply about 1/4 of an inch and press the card board into it. removal will be a messy affair but it will hold until you want to remove it.