In the framework of the Kompaneets approximation the propagation of a shock front ( SF ) in inhomogeneous medium with the power-law density decrease at the exponent n = 2 is investigated .
For this important case corresponding to outer regions of the solar and stellar coronas an unexpectedly simple exact solution clearing a structure of the general solution for an arbitrary monotonic density of medium is found .
Our results for plane-layered medium are compared to the Korycansky one for off-centre explosion in radially stratified medium .
The relation between the solutions in these media are found and a new exact solution for a noncentral explosion in the case of density singularity on the finite radius is received .