Email Security: How to Send Secure Emails for Access and Delivery


June 16, 2024
Written by
Nathalia Velez Ryan
Contributor
Opinions expressed by Twilio contributors are their own
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How to Send a Secure Email for Access and Delivery

We all know the benefits of email, but we should also be aware of the risks. The biggest risks include bad actors who try to take advantage of the potential vulnerabilities of email systems to infiltrate them with phishing attacks, malware, ransomware, and more. 

That’s why email defenses are always getting stronger: to protect recipients and senders alike. 

Email security is crucial for any organization, but it’s especially critical for businesses that send emails to large lists of recipients. And as a sender, you must take steps to ensure all the emails you send are safe. 

This post will cover what email security means, why it’s so important, and how to ensure your emails are secure. 

What is email security?

Email security consists of the processes and tactics email service providers (ESPs), senders, and recipients employ to protect themselves and others from unauthorized access and malicious attacks. The goal of these attacks is typically to steal data or cause problems to an organization with the intent to profit. 

Why is email security important?

One of the benefits of email is that it's an accessible way to communicate and share information. But this also makes email vulnerable to attacks. An attacker with access to your inbox can learn a lot of sensitive information about you or your organization and use it for nefarious purposes. 

Additionally, as a business, bad actors may want to take advantage of the sender reputation and trust you’ve developed to send mass phishing emails.

This is why email security is so important—it helps protect your information and your customers’ and partners’ data. 

Wondering how prevalent email attacks are? Let’s look at some statistics: 

  • Web applications and email are the top 2 ways that bad actors breach organizations (Verizon).
  • Email is at the center of 35% of ransomware incidents (Verizon).
  • Email is the most common delivery method for malware (Verizon).
  • Phishing emails drove at least one person to click on a malicious link in 86% of organizations (Cisco).
  • Phishing tends to peak around the holidays, increasing by 52% in December (Cisco).

Now for the good news. You can employ authentication methods and other defenses to make your emails more secure. We’ll look at what you can do to increase security next. 

Email security best practices: how to secure email

Securing your email communications helps protect your organization and your recipients from data breaches and other threats. Follow these best practices to ensure your business email communications are secure.

1. Use secure login authentication methods 

Security begins when you log into your business accounts, and a simple password doesn’t give you the security you need to protect your business and your recipients. Instead, use one of the following login authentication methods across your organization to keep your emails and data secure. 

Two-factor authentication 

Two-factor authentication (2FA) requires the user to combine 2 types of authentication factors. These factors fall into 3 categories: 

  • Knowledge factors (something you know, like a PIN or password)
  • Possession factors (something you have, like a debit card or mobile phone)
  • Inherence factors (something inherent to you, like a fingerprint)

For example, at an ATM, you present your debit card (possession factor) and enter a PIN (knowledge factor). This type of authentication often occurs via SMS (text) or time-based one-time passwords. Learn more about 2FA

Single sign-on

Single sign-on (SSO) allows users to access multiple applications after authenticating their identity through an identity provider. Often, you find this combined with 2FA.

This type of centrally managed access helps enforce secure passwords while making the login easy for the user—plus, it reduces the risk of account compromise. SSO also makes it easier for teams to securely store and share logins for applications such as ESPs. Learn more about how SSO improves account security and how to set up SSO for Twilio SendGrid.

API keys 

Application programming interface (API) keys—unique codes that identify and authenticate a user—are a more secure alternative to username and password logins. Developers commonly use this method to control access to an API, such as an email API

When you set up an API key, you can select different levels of scope or permissions for each user, allowing you to restrict access to different areas of your account. This way, you limit who can see client data, which we’ll discuss later. 

Learn more about using API keys to connect to Twilio SendGrid’s services and the different levels of access. 

2. Set up sender authentication protocols 

Sender authentication protocols show inbox service providers (ISPs) that you’re a legitimate sender and not a spammer or spoofer. Plus, these protocols make it harder for bad actors to impersonate your brand or leverage your sender reputation to send phishing attacks. 

On the flip side, if you don’t have these protocols in place, you leave yourself open for spammers or impersonators to take advantage of your brand. This could ultimately hurt your reputation or even cause you to end up on a blocklist

The authentication protocols senders should use are: 

3. Use an SMTP server

Simple Mail Transfer Protocol (SMTP) is essentially the pipeline that takes your emails from your server to the recipient’s inbox. An SMTP server processes your email, decides which server it needs to go to, and sends it to that server. The receiving ISP then downloads that message from the server and places it in the recipient’s inbox. 

In addition to relaying your email to its destination, an SMTP server verifies that the email is from an active account, acting as the first line of defense in protecting recipients from illegitimate senders. 

SMTP authentication helps you, as a sender, secure your outgoing email by asking you to log in using an authentication mechanism supported by the server. Learn more about SMTP authentication through Twilio SendGrid

4. Protect data with encryption 

Encryption is one of the most effective ways to protect your email content. This is especially important if you send emails that contain sensitive information about the recipient. 

If you’re just getting started with encryption, our primer on the topic is a great jumping-off point. But essentially, encryption scrambles the data in an email so only authorized users (typically the sender and the recipient) can view it. 

Transport Layer Security (TLS), a type of encryption, protects data as it travels from your server to your email provider’s server. By default, Twilio SendGrid will attempt to deliver your emails via a TLS-encrypted connection as long as the recipient’s email server supports it. This prevents bad actors using passive surveillance devices along the way from viewing the email content. 

Learn more about how Twilio SendGrid protects emails with encryption

5. Limit access to data 

Access to data—especially your recipients' data—should be limited to employees who really need it. This reduces the chances of an email breach becoming a larger issue where data is compromised. There are a couple of ways to accomplish this: 

  • Limit user seats to only those employees who regularly need to access your ESP. Then, regularly audit user seats to ensure you remove inactive users. 
  • Set up different permission levels based on each user’s role, allowing each team member to access the features they need to perform their function while protecting sensitive customer data. Twilio SendGrid users can set permission levels for different team members sharing an account through the Teammates feature

As we move toward a cookieless world, first-party data is more important than ever, making it every business’ responsibility to protect the data entrusted to them by customers. 

6. Train employees on cybersecurity

You’ve likely sat through a few cybersecurity training sessions at your organization. And while seemingly tedious or full of obvious information, these are incredibly important to keep your business secure. 

As an email sender, you might be savvy when it comes to identifying phishing emails. But you need everyone in your organization to be equally savvy to protect your business and your recipients. 

By regularly training employees on how to identify and avoid cybersecurity threats,  you help protect your business and give employees the knowledge they need to protect themselves. 

Send secure emails with Twilio SendGrid

Protecting your data (and your customers’ data) is a top priority for Twilio SendGrid. That’s why we have a variety of email security measures in place, including secure data centers, a dedicated compliance and delivery team, TLS encryption, and operational security standards that restrict who has access to client data. Learn more about how Twilio SendGrid keeps your emails secure.  

Ready to start sending secure emails? Try Twilio SendGrid for free


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