Rational Survivability

* Update:  A few hours after writing this last night, AWS announced they had achieved Level 1 PCI DSS Compliance.* If you pay attention to how the announcement is worded, you’ll find a reasonable treatment of what PCI compliance means to an IaaS cloud provider – it’s actually the first time I’ve seen this honestly described:

Merchants and other service providers can now run their applications on AWS PCI-compliant technology infrastructure to store, process and transmit credit card information in the cloud. Customers can use AWS cloud infrastructure, which has been validated at the highest level (Level 1) of PCI compliance, to build their cardholder environment and achieve PCI certification for their applications.

Note how they phrased this, then read my original post below.

However, pay no attention to the fact that they chose to make this announcement on Pearl Harbor Day 😉

—

Here’s the thing…

A cloud provider can achieve compliance (such as PCI — yes v2.0 even) such that the in-scope elements of that provider which are audited and assessed can ultimately contribute to the compliance of a customer operating atop that environment.  We’ve seen a number of providers assert compliance across many fronts, but they marketed their way into a yellow card by over-reaching…

It should be clear already, but for a service to be considered compliant, it clearly means that the customer’s in-scope elements running atop a cloud provider must also undergo and achieve compliance.

That means compliance is elementally additive the same way “security” is when someone else has direct operational control over elements in the stack you don’t.

In the case of an IaaS cloud provider who may achieve compliance from the “concrete to the hypervisor,” (let’s use PCI again,) the customer in turn must have the contents of the virtual machine (OS, Applications, operations, controls, etc.) independently assessed and meet PCI compliance in order that the entire stack of in-scope elements can be described as compliant.

Thus security — and more specifically compliance — in IaaS (and PaaS) is a shared responsibility.

I’ve spent many a blog battling marketing dragons from cloud providers that assert or imply that by only using said provider’s network which has undergone and passed one or more audits against a compliance framework, that any of its customers magically inherit certification by default. I trust this is recognized as completely false.

As compliance frameworks catch up to the unique use-cases that multi-tenancy and technologies such as virtualization bring, we’ll see more “compliant cloud” offerings spring up, easing customer pain related to the underlying moving parts.  This is, for example, what FedRAMP is aiming to provide with “pre-approved” cloud offerings.  We’ve got visibility and transparency issues to solve , as well as temporal issues such as the frequency and period of compliance audits, but there’s progress.

We’re going to see more and more of this as infrastructure- and platform-as-a-service vendors look to mutually accelerate compliance to achieve that which software-as-a-service can more organically deliver as a function of stack control.

/Hoff

* Note: It’s still a little unclear to me how some of the PCI requirements are met in an environment like an IaaS Cloud provider where “applications” that we typically think of that traffic in PCI in-scope data don’t exist (but the infrastructure does,) but I would assume that AWS leverages other certifications such as SAS and ISO as a cumulative to petition the QSA for consideration during certification.  I’ll ask this question of AWS and see what I get back.

Related articles

• Navigating PCI DSS (2.0) – Related to Virtualization/Cloud, May the Schwartz Be With You! (rationalsurvivability.com)
• Seeing Through The Clouds: Understanding the Options and Issues (thesecuritysamurai.com)
• I’ll Say It Again: Security Is NOT the Biggest Barrier To Cloud… (rationalsurvivability.com)
• PCI 2.0 Allows For Compliant Clouds, Make Sure Your Service Providers Are PCI Compliant (securecloudreview.com)
• What’s The Problem With Cloud Security? There’s Too Much Of It… (rationalsurvivability.com)
• FedRAMP. My First Impression? We’re Gonna Need A Bigger Boat… (rationalsurvivability.com)
• Mixed Mode and PCI DSS 2.0 (brandenwilliams.com)
• The Future Of Audit & Compliance Is…Facebook? (rationalsurvivability.com)
• Incomplete Thought: Compliance – The Autotune Of The Security Industry (rationalsurvivability.com)

Here’s the biggest challenge I see in Cloud deployment as the topic of security inevitably occurs in conversation:

There’s too much of it.

Huh?

More specifically, much like my points regarding networking in highly-virtualized multi-tenant environments — it’s everywhere — we’ve got the same problem with security.  Security is shot-gunned across the cloud landscape in a haphazard fashion…and the buck (pun intended) most definitely does not stop here.

The reality is that if you’re using IaaS, the lines of demarcation for the responsibility surrounding security may in one take seemed blurred but are in fact extremely well-delineated, and that’s the problem.  I’ve seen quite a few validated design documents outlining how to deploy “secure multi-tentant virtualized environments.”  One of them is 800 pages long.

Check out the diagram below.

I quickly mocked up an IaaS stack wherein you have the Cloud provider supplying, operating, managing and securing the underlying cloud hardware and software layers whilst the applications and information (contained within VM boundaries) are maintained by the consumer of these services.  The list of controls isn’t complete, but it gives you a rough idea of what gets focused on. Do you see some interesting overlaps?  How about gaps?

This is the issue; each one of those layers has security controls in it.  There is lots of duplication and there is lots of opportunity for things to be obscured or simply not accounted for at each layer.

Each of these layers and functional solutions is generally managed by different groups of people.  Each of them is generally managed by different methods and mechanisms.  In the case of IaaS, none of the controls at the hardware and software layers generally intercommunicate and given the abstraction provided as part of the service offering, all those security functions are made invisible to the things running in the VMs.

A practical issue is that the FW, VPN, IPS and LB functions at the hardware layer are completely separate from the FW, VPN, IPS and LB functions at the software layer which are in turn completely separate from the FW, VPN, IPS and LB functions which might be built into the VM’s (or virtual appliances) which sit stop them.

The security in the hardware is isolated from the security in the software which is isolated from the security in the workload.  You can, today, quite literally install the same capabilities up and down the stack without ever meeting in the middle.

That’s not only wasteful in terms of resources but incredibly prone to error in both construction, management and implementation (since at the core it’s all software, and software has defects.)

Keep in mind that at the provider level the majority of these security controls are focused on protecting the infrastructure, NOT the stuff atop it.  By design, these systems are blind to the workloads running atop them (which are often encrypted both at rest and in transit.)  In many cases this is why a provider may not be able to detect an “attack” beyond data such as flows/traffic.

To make things more interesting, in some cases the layer responsible for all that abstraction is now the most significant layer involved in securing the system as a whole and the fundamental security elements associated with the trust model we rely upon.

The hypervisor is an enormous liability; there’s no defense in depth when your primary security controls are provided by the (*ahem*) operating system provider.  How does one provide a compensating control when visibility/transparency [detective] are limited by design and there’s no easy way to provide preventative controls aside from the hooks the thing you’re trying to secure grants access to?

“Trust me” ain’t an appropriate answer.  We need better visibility and capabilities to robustly address this issue.  Unfortunately, there’s no standard for security ecosystem interoperability from a management, provisioning, orchestration or monitoring perspective even within a single stack layer.  There certainly isn’t across them.

In the case of Cloud providers who use commodity hardware with big, flat networks with little or no context for anything other than the flows/IP mappings running over them (thus the hardware layer is portrayed as truly commoditized,) how much better/worse do you think the overall security posture is of a consumer’s workload running atop this stack.  No, that’s not a rhetorical question.  I think the case could be argued either side of the line in the sand given the points I’ve made above.

This is the big suck.  Cloud security suffers from the exact same siloed security telemetry problems as legacy operational models…except now it does it at scale. This is why I’ve always made the case that one can’t “secure the Cloud” — at least not holistically — given this lego brick problem.   Everyone wants to make the claim that they’re technology is that which will be the first to solve this problem.  It ain’t going to happen. Not with the IaaS (or even PaaS) model, it won’t.

However, there is a big opportunity to move forward here.  How?  I’ll give you a hint.  It exists toward the left side of the diagram.

/Hoff

Related articles

• Hoff’s 5 Rules Of Cloud Security… (rationalsurvivability.com)
• Hack The Stack Or Go On a Bender With a Vendor? (rationalsurvivability.com)
• The Missing Piece of Cloud Security? (pcworld.com)
• Cloud Adoption Still Struggles With Security Issues in CSO Survey (securecloudreview.com)
• VMware’s (New) vShield: The (Almost) Bottom Line (rationalsurvivability.com)
• If You Could Have One Resource For Cloud Security… (rationalsurvivability.com)