Anti-Spoofing

What Is Email Spoofing and How to Prevent it?

Manipulating email headers to mimic the sender’s address and make people think they’re communicating with someone they know.

This is a brief definition of email spoofing, an infamous fraudulent technique that can cause harm to recipients and those whose electronic addresses have been compromised. Spoofing may happen to individuals and companies alike. One of the world’s most popular shopping platforms, Shein, reported over 1,000 instances of fraudulent emails in April 2024 alone, not to mention the numerous cases affecting small businesses.

Spoofing can have devastating consequences for startups and enterprises by damaging their reputation and making far-reaching data breaches possible. Learn more about this malicious activity and how you can detect and prevent it.

What is email spoofing?

Before developing strategies to eliminate spoofing threats, you should know the enemy you are dealing with. Email spoofing means sending emails from a falsified electronic address. As part of this tactic, cybercriminals create an illusion that the message comes from a different source than it actually does. This is achieved through alterations in the domain or header or the use of fake addresses that look like legitimate ones but differ by one letter or number.

Cybercriminals (in this case, spoofers) aim to convince the recipients of email’s genuine origin, thereby luring them into taking specific actions or disclosing:

  • Financial details
  • Proprietary data
  • Identity information

Here’s a typical example of email spoofing in the financial sector. Clients receive an email that looks like a security alert from their bank or digital payment platform. It says their account will be closed unless they click the provided link or download malware disguised as a helpful guide. People grant spoofers access to their accounts by doing what is required, letting them steal and use their personal information and funds.

When spoofers successfully compromise emails from your organization’s domain, your customers start questioning your cybersecurity level and lose trust. In addition, email spoofing can push your employees, vendors, or partners into making shady transactions or sharing private information.

How dangerous can email spoofing be?

Spoofers’ actions are destructive, whether segregated or integrated into other cyberattack strategies. Even giant brands like Microsoft are not immune to spoofing threats: the company’s customers experienced nearly half of all payment and account-related attacks in 2023. Businesses that use Google Workspace, Microsoft 365, or other SEG services without additional email security may be even more vulnerable to such attacks.

Here are some ways this fraudulent activity can impede the growth of your business: 

  • Business email compromise (BEC). Spoofers often specifically target the company’s email addresses. The aim is to deceive executives, employees, partners, or clients into disclosing confidential information or making unauthorized payments. Over the last 2 years, BEC scams have cost businesses over $2.2 billion.
  • Damaged reputation. If the news about a spoofing case goes beyond your company, clients may associate fake emails with your business and question your communications integrity and cybersecurity practices.
  • Data breaches. Spoofing can be a gateway to more serious data breaches. By employing non-genuine emails, spoofers can use fake addresses to gain access to unprotected systems within an organization for further infiltration and data leaks.
  • Regulatory compliance risks. If your business niche requires compliance with data protection policies, the results of email spoofing attacks can be more costly. Healthcare, finance, and government organizations may face penalties and legal consequences for inadequate cybersecurity.
  • Operational disruption. The aftermath of spoofers’ actions often involves long-term investigations that can cause operational disruptions and drain resources from your core business activities.
  • Phishing attacks. These are some of the most prevalent uses of email spoofing, where cybercriminals impersonate trusted businesses to get their hands on their data. The danger lies in the difference between the two threats. While spoofing isn’t classified as fraud as it only involves email imitation, phishing aims for full-fledged theft.
  • Spreading misinformation. Multiple malicious purposes aside, spoofing attacks help spread non-existing promotions, fake news, and propaganda. This may lead to unwanted repercussions within your company and community.

IT teams should protect their organizations and colleagues from spoofers. Before taking any measures, it is crucial to know how they can compromise your mailing system.

How do cybercriminals forge email addresses?

While companies spend a lot of time eliminating the consequences of spoofers’ actions, hackers find this fraudulent technique incredibly easy to carry out. Email spoofing involves nothing but forging email syntax in one of the following ways.

Fake display name

This spoofing method means what it means: forging the sender’s display name without changing the existing email address. Anyone can do it in Gmail, for example, where a new account can be created with any display name. The underlying email address may not be instantly spotted.

Fake name emails often bypass spam filters because they actually come from legitimate addresses. To identify them, you should double-check the “Mailto:” section whenever you suspect any fraud or implement advanced security protocols to do it for you (more on this later).

Legitimate domains

Spoofers can implement tactics other than stealing someone’s credentials. For example, they can use a valid email address in the “Sender” section. This tactic boils down to manipulating both the display name and address with SMTP servers that allow the manual specification of “To” and “From” addresses.

This simple trick increases the believability of email authenticity. The absence of robust protocols for domain verification only makes things worse for companies with poor cybersecurity.

Similar domains

If the company’s domain is protected, spoofers can create a lookalike version by registering and utilizing a combination of letters and numbers that closely resemble the original. 

Take “@company.com” as an example of a genuine domain. Here’s how it can be faked:

  • Changing the TLD (@company.co) 
  • Replacing a character (@c0mpany.com) 
  • Adding an extra character (@coompany.com) 
  • Removing a character (@compny.com) 

The subtle change in the domain has a high chance of being unnoticed by inattentive recipients. It’s also effective because both employees and CEOs are often too busy to read an email header, and it is easy to take “rn” for “m” or miss a character like “i” in the long domain name while in a rush.

How to stop email spoofing

Advanced anti-spoofing protocols are necessary for all organizations that rely on email for internal or external communication.

SPF

Sender Policy Framework allows domain owners to grant permission to send emails on behalf of their domain to the selected IP addresses. It works like this: you put SPF records in your DNS settings, and the framework approves emails coming from authorized sources. When an email is received, the recipient’s mail server checks if the original domain is in the SPF records. If there’s a match, the email is marked as genuine. 

This protocol is frequently used to prevent email address spoofing by validating the sender’s IP address. However, it is not without security imperfections: it only authorizes the sender’s domain but can’t inspect the contents of the email.

DKIM

To ensure both the sender’s identity and message integrity, businesses can turn to DomainKeys Identified Mail. This technique requires each outgoing email to come with a cryptographic e-signature that lets recipients verify the email origin and exclude the possibility of modifications on its way to the mailbox.

When you set up DKIM, your mail server creates a unique signature for each email it sends out using a key tied to your domain. It acts like a secret code that proves the email comes from you. The public version of this code is shared in your domain’s DNS records. When an email hits the mailbox, the recipient uses the signature from the email header and the DNS public key to mark it as valid.

DMARC

This protocol serves an anti-phishing and domain impersonation purpose by implementing rigorous email authentication policies. Domain-based Message Authentication, Reporting, and Conformance extends the capabilities of SPF and DKIM by granting domain owners full control over email approval.

The recipient’s mail server checks the sender’s domain for a DMARC policy every time a message lands in the inbox. A message that doesn’t pass any alignment fails the authentication process and is rejected. This protocol ensures that only valid and properly aligned emails are delivered.

Anti-spoofing protocols coupled with user awareness

Can you stop email spoofing solely by adopting the recommended protocols and cybersecurity solutions? This is unlikely if your employees are not well-versed in spoofing identification methods and mitigation techniques. Educating your team about the significance of cybersecurity is the best strategy to complement the reliability of SPF, DKIM, and DMARC protocols. 

Guiding your employees on how to check for email spoofing helps them quickly notice and act upon scams. Focus on the dos and don’ts of email security as a proactive reminder for users to verify the sender’s name and address, double-check external links, and report any suspicious emails to IT specialists.

Decisive action for security-conscious businesses

Contact Spambrella for further information about email spoofing prevention and the integration of innovative, AI-based anti-spoofing solutions. We are experts in spotting and getting rid of suspicious emails and can help you navigate through comprehensive security and improved team awareness.

 

Further reading:

Email spoofing: What is it and how to prevent it

Configuring Outbound DKIM Signing