Privacy Issues Discovered in Microsoft Outloook App for iOS and Android

Vulnerabilities in the newly released iOS and Android versions of Outlook have been discovered, with one causing the app to bypass custom Exchange ActiveSync security policies in organizations.

The flaw was discovered by security firm Rapid 7's Dirk Sigurdon, who warns that while there are many security issues with the apps, this one is the most dangerous for enterprises. "Any ActiveSync policy defined on the server is completely ignored," wrote Sigurdson in a post on the security firm's Web site. "Your company can define a sophisticated passcode or encryption policy that will have absolutely no impact on devices if this new e-mail client is used by your employees."

The issue occurs due to Microsoft's cloud service saving and storing user credentials after logging into the service for the first time. The stored credentials allow for the device to automatically connect to a corporate mail network, bypassing some authorization policies set up by IT. The new app, which came out of Microsoft's purchase of Acompli in December, was on the Android and Apple app markets for less than a week before the security holes were discovered.

In response, the European Parliament has completely blocked access to the app by its members and recommends that users uninstall and change their Outlook passwords immediately. Joining the organization in blocking the app was the University of Wisconsin, which cut off access to the Outlook app on Monday.

Sigurdson recommends that other organizations follow suit until a fix from Microsoft is released. "If your organization is dependent on ActiveSync policies in any way, you should immediately block ActiveSync access to Outlook for iOS and Android," said Sigurdson.

Microsoft is aware of the issue and has said in a statement that a PIN lock feature and additional fixes that will resolve corporate Exchange ActiveSync policies will be coming "in the next few weeks."

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Chris Paoli is the site producer for and

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