What Is Email DLP (And Why Should You Care)?

Not a day goes by without some new data breach making top headlines. New threat vectors and constantly expanding attack surfaces put increased pressure on security teams tasked with helping their organizations avoid the massive financial losses (not to mention the bad publicity) that comes from being the most recent victim. But amid emerging cybersecurity dangers is one medium that is anything but new: email.

You don’t have to look far to find examples of hackers targeting company email accounts. The January 2022 attack on the New York Post and Wall Street Journal was facilitated through employee emails, as was the 2016 “Panama Papers” hack that exposed 2.6 terabytes of potentially confidential data.

Attacks like these, combined with intentional and accidental insider data leaks that don’t make it to the news, present a significant danger for modern businesses.

To combat this near-constant threat, businesses turn to email DLP. In this guide, we’ll walk you through what email DLP is, the types of email data loss to look out for, and solutions to help you secure what may be your most vital channel.

What Is Email DLP?

Email DLP stands for email data loss prevention. Email DLP is a type of security software designed to monitor an organization's email communications to prevent leakage of sensitive or potentially damaging data, such as passwords, bank account numbers, credit card numbers, intellectual property, customer information, or business secrets.

Email DLP exists as part of the larger category of data loss prevention (DLP), which includes tools, policies, and strategies for controlling and monitoring data as it moves through any channel or media. And given the ubiquitous nature of email and how it’s used in modern business, email DLP needs to be a central part of any corporate data protection program.

Types of Business Email Data Loss to Monitor

The goal of email DLP is to prevent sensitive data from being accessed by unauthorized parties. To do this, it must be capable of monitoring, identifying, and flagging actions related to the three main types of email data loss:

• Accidental
  In many cases, data leaks happen accidentally. This occurs when an employee attaches the wrong file to an email, sends sensitive data to the wrong recipient, or otherwise mistakenly shares confidential information with a non-authorized party.
• Malicious Insider
  In cases where the data leakage is not accidental, an authorized user within the organization may intentionally and knowingly share emails or email-based data with an external party.
• Mailbox Breach
  Cybercriminals may gain direct access to company email accounts using phishing scams, compromised devices, malicious connected applications, or by simply stealing credentials. Once a hacker has access, they can download the full contents of the email account for later review. This approach can be especially problematic for organizations using traditional email DLP, as the information being compromised is never actually sent (and thus can’t be flagged while in transit). 

How Does Traditional Email DLP Work?

In all likelihood, everyone associated with your company — from the CEO to the intern — has an email account and access to at least some sensitive data. And it’s not difficult (or uncommon) for this data to find its way into outgoing emails. 

Traditional Email DLP deals with this danger by scanning communications and locating sensitive data as it’s sent out. To do this, it relies on a variety of solutions designed to analyze email traffic to identify suspicious, unsafe, or malicious email activity. These approaches include:

• Warnings in the email client - add a visual indicator when composing a message to warn the user if the intended recipient is outside their organization or that the data being sent is sensitive.
• Blocking via network intercept - monitor network traffic for sensitive data and/or unusual recipients and block anything deemed suspicious until reviewed and approved by IT/security. There are a variety of methods for identifying suspicious traffic, from rule-based to machine-learning-based. 
• Dashboarding / Auditing - usually combined with the above approaches, some tools will report findings in a dashboard or audit log to help security teams examine outbound data and find unauthorized sharing.

There is, however, one area of risk that traditional email DLP programs fail to monitor: sensitive messages sitting in an employee's inbox. 

The Problem with Traditional Email DLP

Emails don’t have to be in transit to be dangerous. Often, it’s the inert emails stored in inboxes or filed away that represent a more insidious threat. For example, how much customer data do you think is sitting untouched in your organization’s email accounts right now? What about the number of finance documents in your email archives? Or employee personally identifiable information (PII) in your HR department’s email?  

These motionless emails are easy to disregard but pose a significant threat to your organization's data safety. Data at rest generally doesn’t set off any alarms with email DLP tools. After all, if it’s not leaving the organization, then it’s not a threat, right?

Wrong. Once an unauthorized individual or malicious insider has access to the email account, they don’t necessarily need to send any messages to exfiltrate the data. Instead, they can just screenshot sensitive information or download the account’s contents, and most email DLP tools would never even register the theft.

One approach to curb this threat is focusing on an email retention policy rather than email data protection. But that comes with a problematic tradeoff: every email deleted (while technically no longer a threat to sensitive info) is also a piece of information that the employee can no longer access. This creates potential slowdown and inconvenience for members of the organization. In the case of larger companies, it can represent countless hours lost to resending and re-sharing the same information — which itself may be misdirected or otherwise end up in unauthorized hands.

The danger posed by data at rest in email is becoming increasingly apparent. And given that several high-profile data heists (including those associated with the 2016 Election and the SolarWinds email breach) have been connected to this issue, securing sensitive data within email is a major topic of discussion among IT security teams.

So how can security teams better protect their mailboxes from a data breach? Meet Material Security’s unique Email DLP solution.

Preventing Business Email Data Loss with Material Security

Email DLP from Material Security identifies and protects information sitting at rest in mailboxes, so even if a hacker manages to get inside, it’s not game over. Here’s how it works:

Step 1: Classify Sensitive Data in Mailboxes

The first step to securing sensitive data is to identify it. Material scans company email accounts to locate and label any potentially-dangerous contents (such as PII, financial reports, patents, source code, and more) that may be sitting in employee mailboxes.

Material then provides a detailed breakdown of that sensitive information, including who has most of it and where it may have been shared. This provides valuable insight for security teams into what kind of data at rest they need to be aware of while also clarifying the scope of potential breaches before they occur.

Step 2: Take Action to Secure Sensitive Business Email Data

Once sensitive messages have been identified and classified, Material offers a way to actually secure those messages. Emails containing sensitive information are automatically redacted from the mailbox, secured away from inappropriate access. In order to retrieve the message, the user needs to follow a simple verification step.

Using your existing Single Sign On (SSO), Multi-Factor Authentication (MFA), or a custom verification method, your company can approve or authenticate access requests to these sensitive messages. Once the user request is approved, Material brings back the message directly in the mailbox. This works seamlessly from within your existing email client.

This unique Email DLP solution adds a layer of protection to your most sensitive data sitting in email, helping to ensure that only authorized users are accessing these messages.

Get Started with Material’s Email DLP 

The sensitive data tucked away in your company email accounts needs complete protection — not only when in transit, but also while at rest. Thankfully, Material Security picks up where traditional email DLP stops. Our approach to email DLP adds an additional layer of protection and authentication that goes beyond basic email filtering.

Request time with our team to learn more here.