While the solution to this vulnerability is to patch against the EternalBlue/MS17-010/SMB vulnerability and exploit - (a patch which has been available for 60 days now), Cisco AMP customers are protected against the attack. While Cisco Umbrella (OpenDNS) will stop key requests to encrypt files (provided that TOR servers are blocked - which they should be) it won't stop the spread of malware laterally across the network without AMP or other protective measure. Of course every Windows XP machine (for which there is no patch) would still be infected but wouldn't encrypt while protected by Umbrella.