The vSphere Replication virtual appliance uses VMware Photon OS 4.0 as the guest operating system.
You can apply the latest security update or patch by using the corresponding ISO file.
Before you apply an update or patch to the guest operating system, take into account the dependencies. See Services, Ports, and External Interfaces That the vSphere Replication Virtual Appliance Uses.
To receive the latest security announcements, you can subscribe to the VMware Security Announcements mailing list.