Quote:A spearphishing attack is spoofing Microsoft.com to target 200 million Microsoft Office 365 users in a number of key vertical markets, including financial services, healthcare, manufacturing and utility providers.
 
Researchers at Ironscales discovered the campaign targeting several thousand mailboxes at nearly 100 of the email security firm’s customers, Lomy Ovadia, Ironscales vice president of research and development, said in a report posted online Monday. Other industries being targeted including telecom and insurance companies, he said.
 
The attack is particularly deceiving because it deploys an exact domain spoofing technique, “which occurs when an email is sent from a fraudulent domain that is an exact match to the spoofed brand’s domain,” Ovadia wrote. This means even savvy users who check sender addresses to ensure an email is legitimate might be fooled, he said.
 
The attack is comprised of a realistic-looking email that attempts to persuade users to take advantage of a relatively new Office 365 capability that allows for them to reclaim emails that have been accidentally marked as spam or phishing messages, according to the report. The messages come from sender “Microsoft Outlook.”
 
“Specifically, the fraudulent message is composed of urgent and somewhat fear-inducing language intended to convince users to click on what is a malicious link without hesitation,” Ovadia wrote. “As inferred by the message, the link will redirect users to a security portal in which they can review and take action on ‘quarantined messages’ captured by the Exchange Online Protection (EOP) filtering stack, the new feature that has only been available since September.”
 
Once a user clicks on the link, they are asked to type in legitimate Office 365 login credentials on a fake log-in page controlled by attackers to harvest and likely sell on the dark web, according to Ironscales.