When Dynamic VM Migration Falls Under the Control of VM Users

Security of multi-tenancy in cloud platforms raises a growing interest since research has revealed that the sharing of resources constitutes a vector of vulnerability. In this paper, we examine how one can leverage the sharing of resources, through the manipulation of the amount of resources consumed by VMs, to abusively enforce the dynamic resource management system to trigger VM migrations. This causes waste of resources for the hosting infrastructure and affects performances of VMs. To demonstrate this cross-VM attack, we use VMware's Distributed Resource Scheduler (DRS) in charge of dynamic VM migration management. We perform a detailed analysis of the running of our experimentations by monitoring DRS details during the whole duration of the attack. We explore in various contexts the minimum amount of resources required for the attack to succeed. In our experimentation performed on small clusters, we observe higher vulnerability when the cluster gets larger and when DRS aggressiveness level gets higher. Finally, our experimentations show that the attack can be replayed several times to produce series of VM migrations.