Cosmological nature of the GAMMA-Ray Bursts means that energy discharged from the GRB is greater than energy emitted from supernova explosion, and is enough to make shock reach neighbouring stars or gas clouds and remain strong. It implies the possibility of using the Kompaneets strong explosion approximation for analysis of «hypernovae» remnants shapes, which may correspond to the Gamma-Ray Bursts. Forms of the shock generated by a strong explosion in a medium with quadratic law of density decrease and coming to constant on big distances are analysed. The overflow of density singularity is observed. Obtained results are compared with observational data about hypernova explosions.