Dyre need to secure what matters

Netskope
September 8, 2014 By Rajneesh Chopra

With the iCloud hack in the backdrop raising issues around authentication, another problem has come to the fore – this one affecting Salesforce and going by the name Dyre (alternatively Dyreza). More details are available here – http://goo.gl/s8BSdY.

The first signals of Dyre being circulated on the Internet were seen by researchers back in June, 2014. The vector for spreading this malware has been a phishing email in which the user was lured to click on a link to ostensibly download a file – typically an .exe or a .scr file that is zipped. Once installed, the malware applies a browser hooking technique to intercept traffic before it is encrypted, thereby enabling it to redirect that traffic to a different website than the user intends.

Hackers have set up web pages that look just like that of the intended website and are able to harvest users’ login credentials when they provide them. Since all traffic over an extended period of time is sent to the page put up by the hacker, even information from two-factor auth tokens is available to these malicious actors to use to access targeted cloud apps in real-time. The known variants of the attacks still seem to be bit basic and will most likely be refined further in the future.

Our research team has been monitoring for potential infections related to this malware; none of our customers has yet been affected. What we have seen is growing activity related to getting access to cloud apps through vulnerabilities (http://www.netskope.com/category/vulnerability-advisory/). This is entirely unsurprising; attackers will go where valuables reside. Since enterprises are increasingly using the cloud for variety of reasons – some officially sanctioned by corporate IT and many others not so much – this can put important business data at risk.

With a huge number of devices accessing a growing number of cloud resourced apps from locations no longer within a tightly managed environment, the need for constant monitoring and thoughtful control of these apps is must-have for the enterprise today. Although the observed phishing emails contained links to files in LogMeIn’s Cubby.com file storage service, there is nothing special about Cubby.com; this could have been any of the thousands of  apps that provide file sharing; there are nearly 200 cloud storage apps that we track in the Netskope Cloud Confidence Index™, but one out of five apps across nearly every category we track enables some type of sharing.

It is worth noting that this is not per se a vulnerability in Salesforce nor a flaw in the 2-factor authentication that Salesforce rightly encourages its customers to follow. It’s more about enterprises being responsible for their own users and their own data even when using a cloud app. In this scenario, even encrypting the content stored in app would not protect the data since the authenticated user would have access to the unencrypted data as per policy.

By monitoring all cloud apps that store content – not just a handful of sanctioned ones – and tracking what activities are performed, would an enterprise get a true picture of usage and risk and then looking for anomalous activity? The answer is yes. For example, on a run rate basis, a few users may have been using Cubby.com from a couple of geolocations, but if you suddenly started seeing an increasing number of downloads of zipped files containing .exe and .scr files from this app, that would be considered anomalous behavior and spur you to take immediate action.

The context of who accessed an app from which device and location at what time with what credentials would not only be useful in identifying the infection, but also pinpoint where the remediation needs to be targeted. In addition, you can extend Salesforce’s guidance to customer admins and restrict access from only IP address that are a trusted source for all of your apps that provide content sharing. This would thwart any access attackers may attempt on Salesforce, or any other app, from their own servers.

To determine the current risk and how to best eliminate it in order to safely enable the productive use of cloud apps in your enterprise, contact us for a complimentary cloud risk assessment.