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What is email security?

Email security provides protection against threats like business email compromise and phishing. Learn how to secure your email and environment.

Email security defined

Email security is the practice of protecting email accounts and communications from unauthorized access, loss, or compromise. Organizations can enhance their email security posture by establishing policies and using tools to protect against malicious threats such as malware, spam, and phishing attacks. Cybercriminals target email because it is an easy entry point to other accounts and devices—and it relies in large part on human error. All it takes is one misguided click to cause a security crisis for an entire organization.

Why is email security important?

Email has been a primary communication tool in the workplace for more than two decades. More than 333 billion emails are sent and received daily worldwide—and employees get an average of 120 emails a day. This spells opportunity for cybercriminals who use business email compromise attacks, malware, phishing campaigns, and a host of other methods to steal valuable information from businesses. Most cyberattacks—94 percent—begin with a malicious email. Cybercrime cost more than USD$4.1 billion in 2020, with business email compromise causing the most damage, according to the FBI’s Internet Crime Complaint Center (IC3). The consequences can be severe, leading to significant financial, data, and reputational losses.

The benefits of email security

Businesses of all sizes are realizing the importance of prioritizing email security. An email security solution that safeguards employee communication and reduces cyberthreats is important because it helps to:

  • Protect a company’s brand, reputation, and bottom line. Email threats can lead to devastating costs, operational disruption, and other severe consequences.
  • Enhance productivity. With a robust email security solution in place, businesses can reduce potential disruptions to operations and downtime because of a cyberattack. An effective solution helps security teams streamline response and stay ahead of increasingly sophisticated threats.
  • Ensure compliance with data protection laws such as the General Data Protection Regulation (GDPR) and help circumvent the many intangible costs of a cyberattack such as business disruption, legal fees, regulatory fines.

Email security best practices

In response to the fast-changing email threat landscape, enterprises have established email security best practices to support communication and guard against threats. Top email security best practices include:

  • Educate employees with periodic training to minimize the risk of human error and ensure that employees—often considered a company’s first line of defense—understand the importance of email security.
  • Invest in user awareness training so users can learn how to recognize the signs of a phishing attack and other indicators of malicious intent.
  • Upgrade to an email security solution that provides advanced threat protection.
  • Implement multifactor authentication (MFA) to prevent account compromise. Asking users to provide more than one way to sign into accounts is an easy way to help secure organizational data.
  • Review protections against business email compromise attacks through methods like spoofing and impersonation.
  • Move high-risk processes and transactions to more authenticated systems.

Types of email threats

Organizations face a number of complex email threats from account takeover and business email compromise to spear phishing and vishing. Generally, email threats fall into these group types:

Data exfiltration
Data exfiltration is the unauthorized transfer of data from an organization either manually or through malicious programming. Email gateways help make sure businesses avoid sending sensitive data without authorization, which could lead to a costly data breach

Malware is short for malicious software, and its primary aim is to damage or disrupt computers and computer systems. Common types of malware include viruses, worms, ransomware, and spyware.

Spam is an unsolicited message sent in bulk and without the recipient’s consent. Businesses use spam email for commercial purposes. Scammers use spam to spread malware, trick recipients into divulging sensitive information, or extort money.




Impersonation occurs when cyber criminals pretend to be a trusted person or organization to secure money or data via email. Business email compromise is one example in which a scammer impersonates an employee to steal from the company or its customers and partners.

Phishing is the practice of pretending to be a trusted person or organization to trick victims into disclosing valuable information such login credentials and other types of sensitive data. Different types of phishing include spear phishing, vishing, and whaling.




Types of email security services

Email security services help companies protect email accounts and communication from cyberthreats. The best way for companies to implement email security is to create and maintain a policy for using email and share that with employees so they are aware of email security best practices, Common email security services available for individuals, schools, communities, and organizations include:

  • Detonation capabilities that scan incoming, outgoing, and internal email for malicious links and attachments.
  • Data encryption to secure mail communications from being intercepted by cybercriminals.
  • Image and content control capabilities to scan attached or embedded images and content for malware and blocks them from being downloaded.
  • Spam filters that filter unwanted email like bulk and spam messages.
  • Authentication systems to evaluate the validity of senders.

Email protection

Email threats have become increasingly sophisticated, requiring organizations to implement robust email security systems to protect their data, their reputation, and bottom line. Businesses should consider an email security solution that offers integrated threat protection across apps, devices, email, identities, data, and cloud workloads.

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Frequently asked questions

  • Anyone who uses email needs email security. Individuals, organizations, and businesses who use email are all potential targets for cyberattacks. Without an email security plan and system in place, email users are vulnerable to threats such as data exfiltration, malware, phishing, and spam.

  • Email attacks cost companies billions of dollars a year. The most serious email threats include data exfiltration, impersonation, malware, phishing, and spam because they can have a significant impact on an organization depending on their scope and severity.

  • When an email is sent, it travels through a series of servers before arriving at its destination. A server is a computer system with mail server software and protocols that allow computers to connect to networks and browse the internet.

    Secure emails servers are a necessity for businesses because email-based threats are constantly evolving. Here are a few ways to strengthen the security of your email server:

    • Configure the DomainKeys Identified Mail (DKIM) protocol which lets recipients verify if an authorized domain owner sent an email.
    • Set the mail relay option so it’s not an open relay, which lets in spam and other threats. Configure the mail relay so that it only allows users to send to certain addresses and domains.
    • Set the Sender Policy Framework (SPF) to define which IP address can send emails from your domain.
    • Use Domain Name System Block list (DNSBL or DNS Block list) to block malicious email and domains.
    • Implement Domain-based Message Authentication Reporting & Conformance (DMARC) to monitor your domain.
  • Email encryption is the process of protecting sensitive data in an email by converting it from plain text that is easily read to text that is scrambled with ciphers and readable only to recipients with a key.

  • Here are 5 questions to help test your email security:

    1. Do you use a strong email password that combines uppercase and lowercase letters, numbers, and special characters?

    2. Do you use encryption to send sensitive information?

    3. Have you enabled two-factor authentication which requires entering two separate authentication factors (a password or mobile-generated code)?

    4. Have you installed antivirus software on your devices?

    5. Do you pause and scan attachments and links before opening or clicking on them?

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