A phishing attack using a novel technique to steal credentials from American Express customers was recently found in an email inbox protected using Microsoft s Office 365 Advanced Threat Protection (ATP) by Cofense Phishing Defense Center researchers. The phishing campaign targeted both corporate and consumer cardholders with phishing emails full of grammatical errors but with a small but deadly twist: instead of using the regular hyperlink to the landing page trick, this one used a base HTML element to hide the malicious URL from antispam solutions.
Source: https://www.bleepingcomputer.com/news/security/american-express-customers-targeted-by-novel-phishing-attack/