Much ado about nothing? Millions of Office 365 Users Hit with Zero-day Cerber Ransomware Attack

Posted by Annamaria Montagnese on 01 July 2016 10:10:21 AEST

MailGuard customers can be forgiven for wondering what all the fuss is about. Over the past week, several media outlets have reported on a ransomware attack targeting millions of Microsoft Office 365 users.

The attack which is estimated by some sources to have impacted at least 57% of Office 365 users, took the form of a phishing email that contained a malicious ransomware attachment.


The ransomware demands bitcoin in return for the decryption key, and it was particularly peculiar because the ransom note was accompanied by an audio file with instructions for recovery of the data.

Thousands of businesses are moving to cloud solutions like Office 365 and Google Apps for Work for a range of well understood advantages, like workforce mobility, productivity gains and cost savings. What is less commonly understood is the added security advantages of stacking MailGuard with these solutions.

As a cloud-based solution, MailGuard is an additional security layer that sits in the cloud and stops scams before they reach the user’s environment. MailGuard was successful in protecting its Office 365 customers, blocking this sustained attack throughout Thursday and Friday last week.

If your business has moved to a cloud solution like Office 365 or Google Apps for Work, or if you’re considering the move, reach out to a cloud security specialist at to talk about the added advantages of stacking MailGuard. 


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Topics: Phishing office 365 Cyber Criminals email scam Email Spam Scam Cerber Cerber Malware

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