VMware and Dell|EMC engineering teams have worked closely to develop fixes that will prevent the datastore from being overwritten during an XCopy session. It is recommended to load both the Dell microcode fix and the ESXi patch before re-enabling XCOPY from the host or array.
Patches for ESXi 6.5 and 6.7 have been created that intercepts all attempts to overwrite block 0 on EMC Symmetrix based storage arrays (VMAX/PowerMAX). With the fix, if the array detects an XCOPY attempt to overwrite block 0, the array will reject this attempt and return a custom SCSI sense code to the host. If the ESXi hosts have the patches installed, it will interpret this rejection and fail the XCOPY operation entirely instead of reverting to the software datamover and the XCOPY operation will need to be attempted again.
The Dell EMC fix was released in February 2020 to address this corruption issue. As of May 4, 2020, Dell released microcode enhancement 105521 which supersedes enhancement 104495. This fix is referenced in Dell's DTA 537000: Please read the Dell EMC Knowledgebase article 000002467
VMware has released patches for ESXi 6.5 & 6.7 that protects and reports attempts to alter the VMFS metadata region:
ESXi 6.7: https://docs.vmware.com/en/VMware-vSphere/6.7/rn/esxi670-202004002.html
ESXi 6.5: https://docs.vmware.com/en/VMware-vSphere/6.5/rn/esxi650-202007001.html