A shock mitigator is provided for mitigating physical shock to a joined object. The shock mitigator includes a hollow body capable of being affixed to the object and having two ends defining a volume therein. A cavitating liquid is disposed in the hollow body volume. At least one end cap is slidingly disposed within the hollow body to seal at least one end thereof. When exposed to a physical shock the cavitating liquid changes phase from a liquid to a vapor, absorbing energy from the shock.