On Aviation Analysis Wing website:-
Russian Kinzhal hypersonic missile is based on Iskander-M
Snip:-
Russia's new air launched Kinzhal hypersonic missile is a modified version of the 9M723 missile equipping the mobile Iskander-M surface to surface short range tactical ballistic missile system.
The Kinzhal(Dagger) was revealed by Russian President Vladimir Putin along with five other strategic weapons that supposedly gave Russia an strategic edge over United States.
Dubbed the Kh-47M2 Kinzhal, the air-to-ground missile is initially carried by a MiG-31BM interceptor under its belly hard point.
The massive twin engine MiG-31 remains the fastest operational fighter capable of clocking a top speed close to Mach 3. Cruise speed is 2.35 Mach with a combat range of 1450 km.
The carrier aircraft will serve as the first stage for the Kinzhal, accelerating the missile to a pre-determined altitude and speed that will enable an strategic standoff strike range of 2000 km (1250 miles).