A massive phishing campaign dubbed “EchoSpoofing” exploited a security gap in Proofpoint’s email protection service to dispatch millions of spoofed emails impersonating big entities like Disney, Nike, IBM, and Coca-Cola, to target Fortune 100 companies. […]

from https://www.bleepingcomputer.com/news/security/proofpoint-settings-exploited-to-send-millions-of-phishing-emails-daily/