Mastering Microsoft Defender for Office 365

7

Strengthening Email Security

Previously, we looked at how to protect our organization from inbound spam messages using inbound anti-spam policies. While these policies decrease the attack vectors to our users dramatically, it doesn’t mean these are the only vectors that attackers can exploit in our environment. In many cases, a lack of proper controls for outbound traffic might leave the door open for a free attack venue that can be leveraged by bad actors to remain hidden, with no cost for the attacks leveraged. Closing these gaps via anti-phishing, email authentication, and outbound anti-spam controls is the key to ensuring a more holistic security approach and minimizing the risk of an impact on our organization’s reputation.

This chapter ...