Analyst outfit Gartner has assessed Docker's security – and found the containerisation tool is sound but immature.
Gartner's report, Security Properties of Containers Managed by Docker, published last week, finds “Linux containers are mature enough to be used as private and public PaaS” but “disappoint when it comes to secure administration and management, and to support for common controls for confidentiality, integrity and availability.”
The document also suggests that running Docker inside a hypervisor – advanced by VMware and, to a lesser degree, Microsoft – doesn't necessarily help matters.
“In the majority of cases, Docker might be deployed on top of guest servers that are on top of hypervisors,” writes analyst Joerg Fritsch. “However, except for a further fortification of resource isolation, there is little to be gained from the underlying hypervisor. Docker and containers cannot inherit from the hypervisor what they lack most: secure administration and management features, and support for common controls for confidentiality, integrity and availability. But the hypervisor adds a level of complexity that will need to be managed separately and may cause friction with, for example, evolving SDNs for containerized environments.”
There's better news for the SELinux and AppArmor projects: Fritsch recommends both as essential tools for those keen to run Docker.
The paper also notes that Docker is so new that it's not yet accrued an ecosystem of tools that make it production-ready. Dedicated backup is one weakness (addressed by Asigra on the day this paper emerged), there's no encryption tool for Docker containers – the underlying OS gets the gig at disk level – and security companies are yet to turn their attention to endpoint protection of containers.
Docker also lacks live migration tools, Fritsch says, which makes hypervisors a nice place for it to run but leaves it behind Parallels' Virtuozzo.
Overall, Fritsch seems to say Docker's security features are decent, but that 2015 will likely see the emergence of third-party tools, or additions to Docker itself, that harden the software by improving its manageability and by filling gaps for the kind of functions business expect. Those arrivals will, he suggests, make it easier to operate Docker within the parameters of known best practices and therefore also lessening worries for infosec and governance professionals alike.
That Fritsch also doesn't mention Docker's vulnerabilities seems to make the document a more-than-decent report card for the product. ®