Microsoft Office productivity tools have long been established as the gold standard for business around the world. They hold a significant presence in the market, with an estimated 80 million users using Office 365, the cloud subscription service providing Office applications.
The sudden emergence of Office 365 ransomware puts those users – and their enterprises – at risk. On June 22 at 6:44 a.m., IT security blogger Steven Toole reported the first attack, which was detected by cloud security firm Avanan.
The attack continued for a week, with Microsoft moving to block the malicious attachment on June 23. At least 57% of all Office 365 customers were hit with at least one phishing attempt.