Emergency action defined in CoreRef.sol which is inherited from all the contracts is a good addition which can be used for various purposes (rescuing tokens, executing certain functions, etc.) but it does not use assembly for consuming the returned data which makes it vulnerable to returnbomb attack. Since this action can be used for various purposes, including calling untrusted external contracts this is a real possibility for griefing attack: 
CoreRef.sol#L87-L107
Consider using ExcessivelySafeCall library or assembly to remove the potential vulnerability.
