Email was designed to be as open and accessible as possible. It allows people in organizations to communicate with each other and with people in other organizations. The problem is that email is not secure. This allows attackers to use email as a way to cause problems in attempt to profit. Whether through spam campaigns, malware and phishing attacks, sophisticated targeted attacks, or business email compromise (BEC), attackers try to take advantage of the lack of security of email to carry out their actions. Since most organizations rely on email to do business, attackers exploit email in an attempt to steal sensitive information.
Because email is an open format, it can be viewed by anyone who can intercept it, causing email security concerns. This became an issue as organizations began sending confidential or sensitive information through email. An attacker could easily read the contents of an email by intercepting it. Over the years, organizations have been increasing email security measures to make it harder for attackers to get their hands on sensitive or confidential information.