Email Spoofing 101: Methods of Prevention

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Email Spoofing 101: Methods of Prevention

Email Spoofing

Spoofing, in general, refers to the act of concealing the source of communication. Email spoofing occurs when thieves use emails to deceive receivers by faking an email header. The email receiver is, therefore, duped into thinking the email is from a reliable source and is likely to act on its contents.

Also read: Detect Email Spoofing via Email Headers!

Types of Email Spoofing

Email spoofing can take many different forms:

Name spoofing occurs when an attacker impersonates the identity or display name of a person that the email receiver may trust.

Domain spoofing occurs when attackers imitate the domain of a website the receiver has signed up or subscribed to.

Lookalike domain spoofing occurs when an email address's domain is utilized to visually fool the receiver by sending emails from a similar-looking domain address. For example, if the letter 'o' in the domain address is substituted with a '0’, the receiver is visually duped into thinking the email is from a reliable source.

Certain security methods can assist administrators in protecting their domain from fraudsters. If these protocols are not enabled in the mail servers, there is no one validating the sender's authentication. This makes the domain vulnerable to attacks such as email spoofing, phishing, spam, and other cybercrimes.

SPF, DKIM, DMARC, and BIMI must all be configured to ensure that spoofing emails are recognized before they reach recipients’ inboxes, that attackers do not spoof your domain, and that your emails are sent appropriately to your recipients.

SPF: Protecting sending servers

The first step is to specify which servers will be used. SPF (Sender Policy Framework) is a DNS record that specifies which mail servers are allowed to transmit messages for your domain. This protocol allows you to list the domain name’s authorized servers and IP addresses. This is the first step in the process of verifying your emails.

When a message from your company is delivered, the recipient's mail servers verify that it came from one of the approved domains. The communication will be classified as spam if it does not originate from a trusted domain. SPF records that are incorrectly set might create delivery issues. Depending on the email solution provider, they will generally give configuration instructions.

DKIM: Message signing and authentication

The DKIM (DomainKeys Identified Mail) protocol must also be deployed as a backup. It uses a pair of private and public keys to define the authentication of the email sending domain. The keys are used to sign and confirm the communications' origins.

It is a signature added to your DNS record that includes the signatory's identity. The signature is appended to the header of outgoing emails with the help of a private key. When the recipient's servers receive the email, they examine the source/sender and check whether it has been updated using the public key. The DKIM protocol works in conjunction with SPF to evaluate whether or not an email message should be deemed spam.

DMARC: Confirming the use of SPF and DKIM

SPF and DKIM are followed by DMARC (Domain-based Message Authentication, Reporting, and Conformance). The DMARC record certifies the implementation of the SPF and DKIM protocols, namely the header-to-sending-domain correspondence.

This authentication protocol may be used to check SPF, DKIM, and DMARC configurations. It specifies the procedures to be followed if an email fails to pass certain tests. Reject, quarantine, or do nothing are the three possibilities. The rules can be set to tolerate soft or hard alignment.

In addition, the DMARC protocol generates reports that reveal which communications from your domain have been validated and which have not. This can help you identify potential threats, abuse, or configuration problems.

BIMI: A visual signal

Finally, the BIMI setup (Brand Indicators for Message Identification) is available as a visual authentication protocol. It is a visual enhancement that indicates the sender's identity rather than a technological aspect that strengthens security.

The brand logo is shown next to the email in the recipients’ inbox. If you have SPF, DKIM, and DMARC protocols enabled, and the DMARC policy is set to quarantine or refuse, you can add BIMI. If any of these recommendations are absent, BIMI can’t be implemented.

Although BIMI has been in use since 2019, not all email services (such as Outlook and Office365) support it. Although the concept of strengthening trust by displaying a picture of the sender next to an email is appealing, it does not ensure protection from phishing.

It is no arduous task for an attacker to seek out the picture/logo of a reputed organization, then set up a domain with SPF, DKIM, and DMARC, and send an email to an unsuspecting victim. Users will be much less wary of this email, hence the BIMI will be a disadvantage.

These three procedures reduce the chances of users falling prey to email spoofing attempts. They're also used to safeguard domains that don't send emails. Email spoofing is substantially less widespread now than when these safeguards weren’t implemented. Check out more about DMARC, DKIM, and SPF at EmailAuth.

Original source: https://telegra.ph/Email-Spoofing-101-Methods-of-Prevention-04-06