The proper wording of you question is will he be assassinated.
Putin has been in control of power for a long time in Russia, you can tell that he is surrounded by loyalist who have been with him over the years. Even upon that, on his own is a very cautious and smart man who I believe does not take chances and completely trust everyone. I can bet that he is accessible right now to everyone and only a very handful of individuals in his cabinet know his exact location.