VMware ESXi 6.7 without ESXi670-201811401-BG and VMware ESXi 6.5 without ESXi650-201811301-BG contain uninitialized stack memory usage in the vmxnet3 virtual network adapter which may lead to an information leak from host to guest.
https://www.vmware.com/security/advisories/VMSA-2018-0027.html