There is a security flaw in Google Drive which could allow attackers to spread malicious files as legitimate documents, and also, perform phishing attacks with comparatively higher rate of success.
While the security flaw is known to Google, but still no patch has been released of which Google is hopefully working to contain the vulnerability which resides in the "manage versions" feature in Google Drive that allow users to manage different versions of a file.
The manage versions allow Google Drive users to update an older version of a file, as well as change the way its interface provides a new version of the files having the same file extension; but it turns out that's not actually the case.
How Attackers Could Trick Users Into Installing Malware
According to A. Nikoci, a cyber-security professional who reported the flaw to Google, the affected functionally in Google Drive allows the upload of new version of file with any extension on the cloud storage, even malicious executable.
The legitimate version of the file that is been shared among a group of users can be easily replaced by a malicious file, and when previewed online it won't indicate any newly made changes, but if downloaded can be exploited to infect a targeted system.
And the flaw subsequently leaves the door open for other highly effective spear-phishing campaigns which can take advantage of the widespread use of cloud services like Google Drive to spread malware.
How to Mitigate against any such Malware Threats
Google had recently fixed a security flaw in its Gmail service that could have allowed an attacker to send spoofed emails that mimic Gmail or G Suite users, even with strict DMARC/SPF security policies enabled.
And since cyber-criminals are getting more sophisticated in their crafts to conceal their malicious intentions, it's now more essential that users should keep close watch on suspicious emails, including files on Google Drive; and exercise caution in opening such files to mitigate any possible security risk.