Microsoft 365 is getting a significant security boost

Application Guard for Office
(Image credit: Microsoft)
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Microsoft has announced that Application Guard for Office is now generally available for all Microsoft 365 (opens in new tab) users to help protect them from unsafe files downloaded from the internet that could contain viruses, worms or malware.

Application Guard for Office opens files from potentially unsafe locations in sandboxes to prevent them from gaining access to trusted resources on a user's system. Hardware-based virtualization (opens in new tab) also plays a major role as it is used to isolate these secure containers so that the files opened in them don't infect users with malware.

However, if a user encounters documents from untrusted sources that are not malicious, they can continue working without having to worry about putting their devices, data or their organization at risk.

In addition to protecting users, Application Guard for Office also helps improve Microsoft's own threat intelligence (opens in new tab) capabilities which in turn enhances the company's ability to detect threats and protect its customers.

Application Guard vs. Protected View

Application Guard's power comes from the seamless integration among Windows 10, Microsoft 365 Apps and Microsoft Defender for Endpoint.

Unlike Microsoft's Protected View (opens in new tab) which opens files in read-only mode so that users can see a file's contents and choose to enable editing, Application Guard opens files in an isolated mode that allows users to perform limited editing or printing of untrusted documents without putting their systems at risk. 

Application Guard for Office takes things a step further though by allowing users to read, edit, print and even safe these files without having to re-open them outside of the Hyper-V-based containers used by Microsoft to protect against kernel-based attacks (opens in new tab).

With Application Guard enabled, files originating from the internet, files located in potentially unsafe locations and files blocked by File Block that previously opened in Protected View will now open in Application Guard. Users can also configure Application Guard settings for specific file types such as Outlook attachments, text-based files (.csv, .dif, .sylk) and database files (.dbf).

With more people working from home (opens in new tab) than ever before, Microsoft's decision to make Application Guard for Office generally available makes a great deal of sense as it will allow employees to remain productive even when working with files from untrusted sources.

Via BleepingComputer (opens in new tab)

After working with the TechRadar Pro team for the last several years, Anthony is now the security and networking editor at Tom’s Guide where he covers everything from data breaches and ransomware gangs to the best way to cover your whole home or business with Wi-Fi. When not writing, you can find him tinkering with PCs and game consoles, managing cables and upgrading his smart home.