Email is a popular medium for communication, but also for cyberattacks. Nearly 91% of all cyberattacks start with an email.
This makes it mandatory for domain owners to leverage email authentication to distinguish legitimate emails from malicious ones.
Email authentication is not as complex and technical as it seems, and its benefits are multifold. You can always use an SPF tool or leverage other online resources to help you make the process as easy as it can possibly be.
Key takeaways
- If you do not properly authenticate your emails, you’re inviting hackers to exploit your domain.
- With email authentication, you close the “Everyone welcome” door and create a shield against malicious actors.
- There are two ways to check your email authentication status: manual and automatic.
- Online tools can help you meet your email authentication goals.
What Email Authentication Is
Email authentication helps confirm the identity of email senders while also verifying the legitimacy and safety of emails. It’s an essential, almost indispensable part of modern-day email communications. With the right email authentication setup in place, you can easily avoid phishing emails while also ensuring that no legitimate email ends up in the spam folder.
As important as email authentication is, the majority of domains still do not have proper authentication in place in 2024.
Who Needs Email Authentication
Well, it would be wiser to ask, “Who doesn’t need email authentication?” In an era of ever-evolving cyberattacks, everyone does!
Unauthenticated domain names come with numerous drawbacks and risks.
- Hackers exploit unauthenticated domain names to steal sensitive data and login credentials.
- Unauthenticated domains increase the likelihood of impersonation, spoofing, and phishing.
- When your domain is unauthenticated, it’s easier to be a target and a source of ransomware and unauthorized use.
Why Email Authentication Is So Important
According to Verizon’s DBIR, 90% of all malware is delivered by email. When you authenticate your emails, you designate them as trusted sources for your recipients. This allows the recipient’s server to recognize your messages as legitimate, which in turn increases the likelihood that your emails will be successfully delivered. This can help you:
- Reduce spam
- Prevent spoofing, phishing, and impersonation
- Boost email deliverability
- Comply with Google, Yahoo, and Microsoft sender requirements
After Google started to require that emails sent to a Gmail address have some form of authentication, they saw the number of unauthenticated messages Gmail users receive decrease by as much as 75%.
The 3 Major Email Authentication Protocols
There are many email authentication methods, but there are three of them that build the foundation of email authentication. You can think of them as the three musketeers: SPF, DKIM, and DMARC.
1. SPF (Sender Policy Framework)
SPF (Sender Policy Framework) helps authenticate your emails by allowing you to specify which servers or IP addresses are permitted to send emails on behalf of your domain.
Let’s say “1.12.1.11” is an authorized sender for your domain. If it’s the case, you would include this IP address in your SPF record.
If the email originates from an IP address listed in your SPF record, then it’s considered legitimate and passes SPF authentication. If an email is sent from an IP address not included in your SPF record, the receiving server will flag it as suspicious or potentially reject it.
You can think of SPF as a list of authorized guests at a private event. If the arrivee’s name is not on the list, they will be rejected right at the door!
2. DKIM (DomainKeys Identified Mail)
Now, let’s meet the second of the three musketeers: DKIM. It makes use of cryptographic signatures to verify the integrity of an email. It helps ensure messages remain unmanipulated during transit.
By signing emails with a private key and validating them via a public DNS record, DKIM mitigates risks like man-in-the-middle attacks, where attackers intercept and modify messages.
During setup, the domain owner generates a pair of cryptographic keys:
- Public key: Published as a DNS TXT record for recipient servers to access.
- Private key: Securely stored by the email service provider (ESP) to sign outgoing messages.
When an email is sent, the ESP uses the private key to create a unique cryptographic hash of the message body and headers. This hash is added to the email’s DKIM-Signature header. The recipient’s server retrieves the public key from the sender’s DNS when receiving the email, decrypts the signature, and generates its own hash from the received content. If both hashes match, the email passes DKIM authentication. This confirms that the email wasn’t altered in transit and originated from an authorized source. Think of it like an artist’s signature on a painting; it proves the painting’s origin as well as authenticity.
3. DMARC (Domain-based Message Authentication Reporting & Conformance)
DMARC is the most popular of all musketeers; it helps domain owners manage and control how they want to deal with unauthorized messages.
To configure DMARC, you need to implement either SPF or DKIM.
If you choose the DMARC “none” policy, it will only provide monitoring, and no action will be taken. If you opt for the “quarantine” policy, your email will be lodged in the recipient’s quarantine folder and sent to spam/junk. If you choose the “reject” policy, any email that fails authentication will be outright discarded. Three sub-musketeers, you may say!
If you are wondering which policy is best for you, you can start with the “none” policy for minimum impact on deliverability. Then gradually transition to “quarantine” or “reject” as soon as you are ready to! It all depends on your email authentication needs and goals.
More Friends
SPF, DKIM, and DMARC have other friends too. These include BIMI, MTA-STS, TLS-RPT, etc.
- BIMI (Brand Indicators for Message Identification) enables brands to show their logo in recipients’ inboxes. It gives a professional look while also making your emails look more legitimate and your brand more recognizable.
- The MTA-STS (Mail Transfer Agent Strict Transport Security) protocol enables an SMTP client to check the server identity. Then, the client checks the certificate against a trust store that includes certificates of known servers. The goal is to prevent hackers from tampering with email content or directing the communication to another address.
- TLS-RPT (Transport Layer Security Reports) helps you get comprehensive reports to gain detailed visibility on TLS encryption-related email delivery issues.
How Can You Verify If Your Email Is Authenticated?
There are many ways to check whether or not an email is authenticated. The checking is not an end in itself; it helps you understand your current email authentication status and domain health to take necessary action. It can help you protect your domain from hackers, improve email deliverability, and enhance your domain reputation.
The Manual Check
To manually verify if your emails are authenticated, follow the steps below:
- Start by sending a test message from your domain to an email account you control.
- Open the received email, click the three-dot menu in the top right corner, and select “Show original.” This will open a new tab displaying the full message headers.
- In the message summary, look for the results of SPF, DKIM, and DMARC checks. Do these authentication methods show a “pass?” If yes, congrats, your emails are authenticated!
The Automatic Check
You don’t need to check your email authentication manually, since there is a much faster method: the automatic one!
Let’s see how it works:
- Find a free domain analyzer.
- Input your domain name and click on the action button (in some cases, it might be named “Lookup”).
- You will find a comprehensive report with important email authentication details about your domain. Many domain analyzers also give you a score based on your current email authentication status to give you a quantitative idea of how you’re doing!
How to Verify the Authenticity of Your Email?
Configuring email authentication protocols is actually not as difficult as it sounds! Let’s see how to do it fast and effectively.
Step 1: SPF or DKIM Records before DMARC
Before you configure DMARC, first configure either SPF or DKIM. All you need to do is manually create DNS records for the mentioned protocols and then publish them on your DNS. While this may be a bit challenging to do if you don’t have the technical know-how, you can always use a SPF record generator and a DKIM record generator instead.
Step 2: Time for DMARC
You can also use a DMARC record generator tool to create your first (or second, or… just any) custom record for your domain. Before generating the record, ensure you choose the policy that’s appropriate for your needs. This may be “none,” “quarantine,” or “reject” (remember the sub-musketeers). Don’t forget to publish this record on your DNS!
Step 3: Just Check If All Is Good
Many overlook this step, but checking is equally important as the above two steps. Having the wrong email authentication setup is as bad (or at times even worse) than not having one at all. Ensure you have the proper email authentication setup in place, and you’re good to go!
Summing Up
Email authentication can help protect your domain from malicious actors while simultaneously contributing to better and smoother email deliverability. Whether you choose the manual or automated method for checking your email authentication status, checking it from time to time can help you detect and address security gaps in time. The check may take only a few minutes, but it can save you weeks and months of hard mitigation work.
