Understanding Cloud Access Security Broker Services

Over the past 30 years, we the IT Security team have been promoting and building a "Defence in Depth" strategy to protect our corporate assets. 

This methodology was predicated on the fact that we need to assure our employees, customers, and shareholders that we were able to provide adequate Confidentiality, Integrity, and Availability (The CIA-Triad)  for the sensitive data/intellectual property residing in physical  data centers. 

We have installed Firewalls, Intrusion Prevention, AntiMalware,  Data Loss Prevention, Secure Email, VPN, etc... All with the intent on providing a stack of security capabilities to protect data withing our corporate network.  Within our corporate data centers.

Simultaneously, our lines of business are becoming more agile, more complex, and more attune to services available "in the cloud".  Shadow IT is the new trend.  Lines of Business can and are spinning up new services at an aggressive rate to keep up with their online competition. Our ability to manage them "technically" as opposed to by policy has been almost non-existent.

We as Security Experts, are scrambling to augment our "bricks and mortar" based Defense in Depth strategy with Cloud Services, but the path is not presently clear.

Very recently, a niche market has developed to fill this void. Several vendors identifying themselves as Cloud Access Security Brokers (CASBs) have defined a strategy to mitigate this problem.  CASBs are either on-premise, or cloud-based (or both) security policy enforcement points. Placed between your end users and the various cloud service providers, they can inspect traffic, manage and enforce policy, alert on anomalous behavior, and in most cases provide some level of DLP enforcement.

Either leveraging existing Single Sign On providers, or corporate Active directory services, these Cloud Access Security Brokers can identify individuals' access into Cloud Service Providers that are affiliated with the broker. Currently these number in the  hundreds if not thousands. For "Sanctioned" Cloud Applications (those services for which your enterprise has procured directly) end user access can be strictly enforced by context:

• Who you are (Role based access)
• Where you are coming from (corporate network, public Internet, wifi, geographic region)
• What device you are using (Corporate laptop, Home PC, Tablet or phone)
• What time of day you're working (Are you authorised to work during this time?)

This Context Awareness also allows the CASB providers to employ heuristic analysis on Cloud bound traffic, to do some form of anomaly detection to identify malicious or erroneous traffic.  This is an area that they are all investing heavily in today.
  Most of the Cloud Access Security Brokers provide granular encryption, but only three provide  Tokenization of your Corporate Data in the Cloud. This can be as coarse as entire records or documents, or as fine grained as a field in a form.  Adallom has also  leveraged the Right's Management functionality of Checkpoint's Capsule to secure data in the cloud, while allowing trusted collaboration.

For more on Tokenization vs encryption, please see my articles: Tokenization as a companion to Encryption and Toronto based PCI Compliance upstart Blueline brings holistic solution to Voice-Web-POS

One of the strengths of some of the Cloud Access Security Brokers is the ability to identify and report on employee access to  "Shadow IT" cloud services.  "Shadow IT" are described as services that the corporation has not subscribed to as a whole, or has not specifically provisioned for the user in question.  These typically include Cloud Storage facilities like Box or Dropbox.   Again, if the CASB has an affiliation with the cloud service provider, these can be managed by policy, otherwise they can be flagged and alerted on to your security operations team for manual remediation.

Several of these CASBs provide on-premise inspection and policy gateways to augment your corporate network controls and provide definitive logical access control to the cloud services from within the corporate network.  These on-premise gateways complement the cloud based CASB services and provide for a hybrid view of data movement.

Since their emergence in 2012, CASBs have grown in importance and today are the primary technical means of giving organizations more control over SaaS security. This technology will become an essential component of SaaS deployments by 2017.

 By 2016, 25% of enterprises will secure access to cloud-based services using a CASB platform, up from less than 1% in 2012, reducing the cost of securing access by 30%.

- Gartner, The Growing Importance of Cloud Access Security Brokers

Gartner has defined the four pillars of CASB as:

 Visibility, Data Security, Compliance and Threat Prevention.

 As of this time, there are about twelve companies playing in this space. I would like to highlight the leaders at the moment. 

(In alphabetical order, and in their own words. ie: pilfered from their websites.)

Adallom delivers an extensible platform to secure and govern cloud applications. In addition to discovering almost 13,000 cloud services in use, Adallom offers comprehensive controls for data sharing, data security, DLP, eDiscovery and access control. The Adallom platform also integrates with existing on-premises solutions such as SIEMs, MDMs, NACs and DLPs. Adallom has identified new malware attacks in the wild, including a Zeus variant attacking Salesforce, and an identity token hijacking vulnerability affecting Office 365.  On April 21st, Adallom announced an HP partnership where its platform will be resold on the HP price list, and offered with the HP Enterprise Security Products and Enterprise Security Services portfolio. https://www.adallom.com 

https://www.crunchbase.com/organization/adallom

Bitglass the Total Data Protection company, is a Cloud Access Security Broker, founded in 2013, that delivers innovative technologies that transcend the network perimeter to deliver total data protection for the enterprise - in the cloud, on mobile devices and anywhere on the internet.  Bitglass delivers the security, visibility, and control that IT needs to enable mobile and cloud in the workplace, while respecting user privacy.

https://www.crunchbase.com/organization/bitglass

CipherCloud is a cloud security software suite that encrypts data during the upload process, and decrypts during download. The encryption keys used for this process remain within your business network; thus, unauthorized users accessing data in the cloud will only see indecipherable text.
CipherCloud also comes with built-in malware detection and data loss prevention. There are specific builds for commonly used cloud applications such as Salesforce, Office 365, Gmail and Box, as well as a variant that can be configured to work with any cloud-based applications your business uses.

https://www.crunchbase.com/organization/ciphercloud

Netskope is a leader in cloud app analytics and policy enforcement. Netskope aims to eliminate the catch-22 between being agile and being secure and compliant by providing visibility, enforcing sophisticated policies, and protecting data in cloud apps.  
Netskope is a service that discovers and monitors cloud apps and shadow IT used on your network. Netskope monitors users, sessions, shared and downloaded content as well as the shared content details, and provides detailed analytics based on this information.

https://www.crunchbase.com/organization/netskope
 

Perspecsys' AppProtex Cloud Data Protection Platform provides a flexible cloud data control platform that enables organizations to identify and monitor cloud usage and then encrypt or tokenize data that it does not want to put in the cloud “in the clear”.  The Platform intercepts sensitive data while it is still on-premise and replaces it with a random tokenized or encrypted value, rendering it meaningless should anyone outside of the company access the data while it is being processed or stored in the cloud.

https://www.crunchbase.com/organization/perspecsys

Skyhigh Networks enables organizations to adopt cloud services with appropriate security, compliance, and governance. Skyhigh supports the entire cloud adoption lifecycle, providing unparalleled visibility, analytics, and policy-based control. Specifically, Skyhigh shines a light on Shadow IT by giving a comprehensive view into an organization’s use and risk of all cloud services. Skyhigh analyzes the use of all cloud services to identify anomalous behavior indicative of security breaches, compromised accounts or insider threats. Finally, Skyhigh enforces the organization's policies on the use of over 12,000 cloud services by providing contextual access control, structured and unstructured data encryption and tokenization, data loss prevention, and detailed cloud activity monitoring for forensic and compliance purposes.

https://www.crunchbase.com/organization/skyhigh-networks

Zscaler is leading two fundamental transformations in the world of IT security. First—the shift from on-premise hardware appliances and software to Security as a Service. Second—the transition from point security solutions to broad unified security and compliance platforms. Both transformations exactly parallel what has happened in every other sector of information technology—CRM, ERP, HR, eCommerce, and personal productivity—all have evolved from on-premises point applications to comprehensive cloud—based platforms. 

https://www.crunchbase.com/organization/zscaler 

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While conducting this review of the CASB market, I looked at a number of Security Controls that I would expect a mature Access Broker to provide. I've laid this out in accordance with Gartner's four pillars: 

 Visibility, Data Security, Compliance and Threat Prevention.

 

If you think I have omitted your favorite Cloud Access Security Broker, or have mis-represented a control above, please have them forward details to me including their position on each of the items in the above controls list.  After validating each, I will gladly amend the list.

Although the CASB market space is still in it's infancy, the main players have done a good job defining - and meeting - most of the requirements of an off-premise security service. 
I'm interested to see what happens to this space over the next three years.   My money is on convergence of CASB, SSO, and Mobile Security providers.



Also Read: 

Standing at the Crossroads: Employee Use of Cloud Storage.




References:

Gartner: The Growing Importance of Cloud Access Security Brokers
http://www.computerweekly.com/news/2240223323/Cloud-access-brokers-top-security-technology-says-Gartner
Gartner: Emerging Technology Analysis: Cloud Access Security Brokers
http://www.ciphercloud.com/2014/09/30/public-cloud-security-demands-cloud-access-security-broker-casb/
https://www.netskope.com
Bitglass: The Definitive Guide to Cloud Access Security Brokers
CipherCloud looks to stay at the head of the cloud security class 
Ciphercloud: 10 Minute Guide to Cloud Encryption Gateways
Ciphercloud: Cloud Adoption & Risk Report in North America & Europe – 2014 Trends
NetworkWorld: How the cloud is changing the security game
Adallom: The Case For A Cloud Access Security Broker
Adallom: Cloud Risk Report Nov 2014
Check Point Capsule and Adallom Integration 
HP - Adallom: Proven Cloud Access Security Protection Platform 
Adallom : to Offer Comprehensive Cloud Security Solution for Businesses With HP 
PingOne - Skyhigh: PingOne & Skyhigh Cloud Security Manager
ManagedMethods: Role of Enterprise Cloud Access Security Broker
Standing at the Crossroads: Employee Use of Cloud Storage. 
Cloud Computing: Security Threats and Tools 
SC Magazine: Most cloud applications in use are not sanctioned  

PCI DSS Cloud Computing Guidelines - Overview

The PCI Security Standards Council  has just published (02'07'2013) an Information Supplement: 

 PCI DSS Cloud Computing Guidelines



According to their press release:

"One of cloud computing’s biggest strengths is its shared-responsibility model. However, this shared model can magnify the difficulties of architecting a secure computing environment," said Chris Brenton, a PCI Cloud SIG contributor and director of security for CloudPassage. "One of this supplement’s greatest achievements is that it clearly defines the security responsibilities of the cloud provider and the cloud customer. With PCI DSS as the foundation, this guidance provides an excellent roadmap to crafting a secure posture in both private and public cloud."

So, first things first: 

This is an information supplement, not intended to replace the PCI Data Security Standard (DSS), but rather to enhance the work done during the development of the Virtualization Guidelines in June of 2011. They have acknowledged the move toward Cloud Services, and have created a set of guidelines to allow businesses to remain PCI Compliant while moving their workloads to the Cloud.

To diferentiate roles and responsibilities between Cloud Customer and Cloud Service Provider, the PCI Security Standards Council leverages the definitions of Cloud Computing provided by NIST to outline the common deployment models:

• Private cloud. The cloud infrastructure is provisioned for exclusive use by a single organization comprising multiple consumers (e.g., business units). It may be owned, managed, and operated by the organization, a third party, or some combination of them, and it may exist on or off premises.
• Community cloud. The cloud infrastructure is provisioned for exclusive use by a specific community of consumers from organizations that have shared concerns (e.g., mission, security requirements, policy, and compliance considerations). It may be owned, managed, and operated by one or more of the organizations in the community, a third party, or some combination of them, and it may exist on or off premises.
• Public cloud. The cloud infrastructure is provisioned for open use by the general public. It may be owned, managed, and operated by a business, academic, or government organization, or some combination of them. It exists on the premises of the cloud provider.
• Hybrid cloud. The cloud infrastructure is a composition of two or more distinct cloud infrastructures (private, community, or public) that remain unique entities, but are bound together by standardized or proprietary technology that enables data and application portability (e.g., cloud bursting for load balancing between clouds).

Within each of these you would have service models  (Software As A Service SaaS, Platform As A Service PaaS, and Infrastructure As A Service IaaS).

They then clearly define the relationships between Customer and Service Provider.  Of particular note:

The level of security responsibility across the cloud service models generally migrates towards the client as the client moves from a SaaS model (least client responsibility) to an IaaS model (most client responsibility). The greatest level of responsibility for the CSP to maintain security and operational controls is present in the SaaS service model.

  

They then thoroughly discuss the PCI related responsibility each side may have from the physical data center of the provider, through the network, storage, virtualization layers, Operating System, Application Stack, presentation layer, and finally data. The following table is one of the examples they provide:

As expected, considerable care is placed around the discussion of segmentation.

It is the Customer's responsibility to ensure that the Cloud Service Provider has adequately provided "an equivalent level of isolation as that achievable through physical network separation."  Critical to this discussion is the isolation of each layer (network, virtualization, Operating System, and Data)  from other Customers of the Provider. 

Once any layer of the cloud architecture is shared by CDE (Cardholder Data Environment) and non-CDE environments, segmentation becomes increasingly complex. This complexity is not limited to shared hypervisors; all layers of the infrastructure that could provide an entry point to a CDE must be included when verifying segmentation.

Recommendations for minimizing and simplifying PCI DSS scope in a cloud environment include:

Don’t store, process or transmit payment card data in the cloud.

Failing that:

• Implement a dedicated physical infrastructure that is used only for the in-scope cloud environment.
• Ensure Segregation of CDE and non-CDE environments
• Ensure Segregation of Service Provier Customers
• Minimize reliance on third-party CSPs for protecting payment card data.
• Do not transmit data in clear text
• Do not store data in clear text
• Maintain control of your encryption keys (isolate encryption/decryption/key management from your cloud)
• Validate PCI DSS controls regularly

  There are several case studies described in the document to assist in understanding the accountabilities/responsibilities in various Cloud Provider models.

All in all, this is a clear and concise read which go to great lengths to help assess the requirements to meet when selecting a Cloud Service Provider to support your PCI environment.