"Pass-By-Reference" inputs to a multicast RPC can crash

Passing a parameter by reference for an RPC does not seem to be a supported operation, and UnrealHeaderTool will already throw an error if a networked UFUNCTION includes any OutParms. However, users can still select the "Pass-By-Reference" checkbox for inputs to replicated blueprint events, creating RPCs with OutParms. There is some handling for OutParms in the NetDriver with NetDriverInternal::CopyOutParametersToLocalParameters, but if an input to a multicast RPC has "Pass-By-Reference" checked, this can  lead to memory issues and crashes if the RPC is sent to more than one client.

See linked UDN with repro project