Trust in your cloud provider is key, when you move more data there than data classified as public. Then come all the solutions encrypting your data, which keeps it safe but at the end of the data loses search.
A real problem I have not seen a solution. Additionally we run into the problem protecting one customer from the other in a multi-tenant environment.
We are looking into solutions to wrap a VM for protection without installing an agent. It seems to work fairly well but still leaves the problem of a malicious administrator on the table.
Definitely worth keeping an eye on
- Microsoft Research thinks Haven might be the answer to cloud storage security problems (betanews.com)
- Is Haven the answer to cloud security problems? (itproportal.com)
- Is a Safer Cloud on the Horizon? (research.microsoft.com)