You can't prevent employees from snapping up iPads and Droid phones, even if you wanted to. Sixty-five percent of respondents to our InformationWeek 2011 Mobile Device Management and Security Survey predict that the number of employee-owned devices accessing company data will increase. What you can do is use your leverage when they want to connect to business systems by asking them to run mobile device management (MDM) software, which can enforce corporate policies and provide features such as device tracking and remote wiping.

Even though it's a fair trade, IT must still tread carefully, because the enterprise is permitting access by a device it doesn't own. A key challenge is to craft policies that provide adequate security assurance while at the same time respecting the owner's personal application and usage choices. After all, users who shell out hundreds of dollars for slick new tablets are going to install whatever applications they want.

The tension between ownership and protection often boils over when IT tries to push policies that whitelist or blacklist apps in response to attackers unleashing malicious software that targets mobile platforms.

Dangerous Markets

This problem is particularly acute for Android, which has an enormous user base and a flexible app market. Tim Wyatt, principal security engineer at Lookout Mobile Security, says Android's open application distribution model allows apps to be pulled from multiple markets--including repackaged versions of legitimate apps. Malware is also on the Android Market itself. For example, according to Lookout's research, when DroidDreamLight emerged as a threat, it was found to be repackaged in 20 utility, nine porn, and five game apps in the Android Market. To make matters worse, the Android model relies on a user's ability to evaluate the permissions an app is requesting at install time.

Apple imposes stricter control over its own app market, but it's not a foolproof system. For instance, security researcher Charlie Miller developed a proof-of-concept malware app, called InstaStock, that made it into Apple's App Store--at least for a limited time.

So what's an IT policymaker to do? Risk-averse organizations will likely insist on tight policies that include app whitelisting and accept that they'll get pushback from users. Those with more liberal policies or that offer personal-device access to only nonsensitive data may elect to sidestep the issue, for now. Our advice: No matter your policy, use an app malware detection system, available from vendors such as McAfee, Symantec, and smaller players such as Lookout, that can be pushed as a mandatory installation via an MDM platform.

As with conventional antivirus packages for PCs, vendors for mobile platform AV must be able to demonstrate accurate detection and fast updates. If something is discovered, anti-malware systems should warn IT. Most MDM systems will allow you to quarantine an infected device until it's remediated.

Grant Moerschel is co-founder of WaveGard, a consulting firm. Write to us at iwletters@techweb.com.