How to prevent email spoofing

Email spoofing is a growing problem for an organization’s security. Spoofing occurs when a hacker sends an email that appears to have been sent from a trusted source/domain. Email spoofing isn’t a new concept. Defined as “the forgery of an email address header in order to make the message appear to be sent from someone or somewhere other than the actual source,” it has plagued brands for decades. Whenever an email is sent, the From address doesn’t display what server the email was actually sent from—instead it displays whatever domain is entered during the address creation process, thereby raising no suspicion among email recipients.

With the amount of data passing through email servers today, it should come as no surprise that spoofing is an issue for businesses.At the end of 2020,  we found that phishing incidents rose by a staggering 220% compared to the yearly average during the height of global pandemic fears.. Since not all spoofing attacks are carried out on a large scale, the actual number could be much higher. It is 2021, and the problem seems to be only worsening with each passing year. This is why brands are availing of secure protocols to authenticate their emails and steer clear of the malicious intentions of threat actors.

Email Spoofing: What Is It and How Does It Work?

Email spoofing is used in phishing attacks to trick users into thinking the message came from a person or entity they either know or can trust. A cybercriminal uses a spoofing attack to trick recipients into thinking the message came from someone it didn’t. This lets attackers harm you without letting you trace them back. If you see an email from the IRS saying that they sent your refund to a different bank account, it may be a spoofing attack. Phishing attacks can also be carried out via email spoofing, which is a fraudulent attempt to obtain sensitive information such as usernames, passwords and credit card details (PIN numbers), often for malicious ends. The term comes from ‘fishing’ for a victim by pretending to be trustworthy.

In SMTP, when outgoing messages are assigned a sender address by the client application; outbound emails servers have no way to tell if the sender address is legitimate or spoofed. Hence, email spoofing is possible because the email system used to represent email addresses does not provide a way for outgoing servers to verify that the sender address is legitimate. This is why large industry players are opting for protocols like SPF, DKIM and DMARC to authorize their legitimate email addresses, and minimize impersonation attacks.

Breaking Down the Anatomy of an Email Spoofing Attack

Each email client uses a specific application program interface (API) to send email. Some applications allow users to configure the sender address of an outgoing message from a drop- down menu containing email addresses. However, this ability can also be invoked using scripts written in any language. Each open mail message has a sender address that displays the address of the originating user’s email application or service. By reconfiguring the application or service, an attacker can send email on behalf of any person.

Let’s just say that now it is possible to send thousands of fake messages from an authentic email domain! Moreover, you don’t have to be an expert in programming to use this script. Threat actors can edit the code according to their preference and begin sending a message using another sender’s email domain. This is exactly how an email spoofing attack is perpetrated.

Email Spoofing as a Vector of Ransomware

Email spoofing paves the way for the spread of malware and ransomware. If you don’t know what ransomware is, it is a malicious software which perpetually blocks access to your sensitive data or system and demands an amount of money (ransom) in exchange for decrypting your data again. Ransomware attacks make organizations and individuals lose tons of money every year and lead to huge data breaches.

DMARC and email authentication also acts as the first line of defense against ransomware by protecting your domain from the malicious intentions of spoofers and impersonators.

Threats Involved for Small, Medium and Large Businesses

Brand identity is vital to a business’s success. Customers are drawn to recognizable brands and rely on them for consistency. But cybercriminals use anything they can to take advantage of this trust, jeopardizing your customers’ safety with phishing emails, malware, and email spoofing activities. The average organization loses between $20 and $70 million a year due to email fraud. It is important to note that spoofing can involve trademark and other intellectual property violations as well, inflicting a considerable amount of damage to a company’s reputation and credibility, in the following two ways:

  • Your partners or esteemed customers can open a spoofed email and end up compromising their confidential data. Cybercriminals can inject ransomware into their system leading to financial losses, through spoofed emails posing to be you. Therefore the next time they might be reluctant to open even your legitimate emails, making them lose faith in your brand.
  • Recipient email servers can flag your legitimate emails as spam and lodge them in the junk folder due to deflation in server reputation, thereby drastically impacting your email deliverability rate.

Either ways, without an ounce of doubt, your customer-facing brand will be on the receiving end of all complications. Despite the efforts of IT professionals, 72% of all cyber attacks begin with a malicious email, and 70% of all data breaches involve social engineering tactics to spoof company domains – making email authentication practices like DMARC, a critical priority.

DMARC: Your One-Stop Solution against Email Spoofing

Domain-Based Message Authentication, Reporting and Conformance (DMARC) is an email authentication protocol which when implemented correctly can drastically minimize email spoofing, BEC and impersonation attacks. DMARC works in unison with two standard authentication practices- SPF and DKIM, to authenticate outbound messages, providing a way to specify to receiving servers how they should respond to emails failing authentication checks.

Read more about what is DMARC?

If you want to protect your domain from the malicious intentions of spoofers, the first step is to implement DMARC correctly. But before you do so, you need to set up SPF and DKIM for your domain. PowerDMARC’s free SPF and DKIM record generators can aid you in generating  these records to be published in your DNS, with a single click. After successfully configuring these protocols, go through the following steps to implement DMARC:

  • Generate an error-free DMARC record using PowerDMARC’s free DMARC record generator
  • Publish the record in your domain’s DNS
  • Gradually move to a DMARC enforcement policy of p=reject
  • Monitor your email ecosystem and receive detailed authentication aggregate and forensic (RUA/RUF) reports with our DMARC analyzer tool

Limitations to Overcome While Achieving DMARC Enforcement

You have published an error-free DMARC record, and moved to a policy of enforcement, and yet you are facing issues in email delivery? The problem can be far more complicated than you think. If you didn’t already know, your SPF authentication protocol has a limit of 10 DNS lookups. However, if you used cloud-based email service providers and various third-party vendors, you can easily exceed this limit. As soon as you do so, SPF breaks and even legitimate emails fail authentication, leading your emails to land in the junk folder or not being delivered at all.

As your SPF record gets invalidated due to too many DNS lookups, your domain again becomes vulnerable to email spoofing attacks and BEC. Therefore staying under the SPF 10 lookup limit is imperative to ensure  email deliverability. This is why we recommend PowerSPF, your automatic SPF flatenner, that shrinks your SPF record to a single include statement, negating redundant and nested IP addresses. We also run periodical checks to monitor changes made by your service providers to their respective IP addresses, ensuring that your SPF record is always up-to-date.

PowerDMARC assembles a range of email authentication protocols like SPF, DKIM, DMARC, MTA-STS, TLS-RPT and BIMI to give your domain a reputation and deliverability boost. Sign up today to get your free DMARC analyzer.