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Blog Uncategorized Avoiding Proxy Creep with an Instance-Aware CASB
Jul 13 2016

Avoiding Proxy Creep with an Instance-Aware CASB

One of Netskope’s more popular taglines is “Allow is the new Block.” Many times, customers and prospects will ask me what that means and how it impacts them. To answer, I walk them through their usage of cloud apps, and more often than not, we discover that they have more exclusions in their proxies or firewalls than policies meant to stop traffic. This has created a gap where many cloud apps are allowed into an ecosystem than initially intended – sometimes called “proxy creep.”

What is proxy creep? Also known as “exception sprawl,” it happens when exclusion rules have allowed shadow IT applications in your network. A great example is many times companies work with external vendors, and those vendors have a corporate sanctioned file-sharing site. Those include Dropbox, Box or Office 365. Proxy or firewall exclusion will be set to allow the cloud storage of the vendor. This in turn allows all the other users to access that application, as well as personal version of the corporate-sanctioned app to be used. Unknowingly, proxy creep has been created and new applications are inside your ecosystem.

How can you identify if you have proxy creep? Do you have a good process for handling your exceptions (for example, do you have good controls in place for limiting the exception to a small group of individuals or adhering to a time limit? Have you tried blocking by category and then creating an exception for the application? If you bypass the apps, do you have any *.URL rules applied? Can you easily access URLs like, or Does your company use an online customer relationship management (CRM) solution like How is that CRM allowed? Did you set a single URL bypass or is a whole category allowed? These are just a few questions to ask yourself or your IT team in regards to cloud applications.

Did you know almost every enterprise application today has a “freemium” consumer version available for free? It is a great sales tactic for vendors to get users on the platform and using the application, then coming back to the IT organization showing high usage and offering an enterprise license. For the users’ part, they will  claim (often rightly) that the app makes them more productive, which every employer wants to hear.

Quickly the conversation turns into how to we secure those applications and block everything else. As we have all learned, it is rarely good to outright block as this can hurt corporate culture and push employees to find new ways around the block (often with lower-quality, less secure apps). The best solution is having an instance-aware cloud access security broker (CASB). Instance awareness allows the security team to apply a rule set around the corporate-sanctioned version of the app, whether cloud storage, CRM, or other ecosystem applications. You may enforce a policy in your corporate-sanctioned version of the app in which you allow upload and download of all files, whereas you may have a more restricted set of policies in the freemium versions of the same app, including more restrictive cloud data loss prevention (DLP) rules for certain file types or meeting certain cloud DLP profile criteria.

Implementing a CASB solution has been noted as Gartner’s #1 information security priority for 2016. A CASB cannot only monitor the cloud applications but also Infrastructure as a Service (IaaS) and Platform as a Service (SaaS) providers. This will give your team the ability to extend your reporting and policies outside of your traditional network.