Email is one of the most popular online correspondence methods, especially for businesses. However, the majority of malware installed on compromised networks originates from an email attachment. Without the proper security measures, it can quickly act as a gateway for email, phishing attempts, and malicious links and attachments.
See Also: PCI Compliance and Email Security
Cybercriminals see your company email accounts as a possible source of valuable business and consumer data. Applying best practices for email security helps prevent malicious people from exploiting email as a way to access your data and systems and can help reduce your risk of email-based cyberattacks.
Most organizations rely heavily on emails for their daily business communication, but email remains one of the most common vectors businesses are attacked. This is why it is essential to implement email security best practices.
Cybercriminals can easily exploit overlooked vulnerabilities of corporate email security using distributed denial of service (DDoS), phishing attacks, malware, ransomware, and employee errors.
Data loss and leakage of sensitive information related to downtime, a company’s finances, intellectual property, employee, and customer information may be caused by inadequate email protection. Losing control of such confidential documents will result in a loss of sales, market share, fines, and reputational harm.
See Also: How DLP Helps with PCI DSS Compliance
Unique, standalone email security solutions are available to combat all types of attacks. On the other hand, IT departments need complete visibility and control over the company’s overall email security strategy and safety.
This article outlines core business email security best practices for employees to help you build a strong layer of email protection and maintain email continuity.
Essential Email Security Best Practices
The following email security best practices can help protect your company’s email accounts from email-borne cyberattack risks, such as spoofing and malicious attachments.
1. Train Your Staff on Cyber Security Awareness
Cybersecurity awareness training is an integral part of every effective cybersecurity policy, yet it’s sometimes ignored. Every employee should be provided with comprehensive cybersecurity awareness training regardless of their seniority.
Whether you are an organization operating on more than one continent or a small business that has just discovered yourself, you are the target of cyberattacks. It is a common misconception that small businesses are safe from cybercrime. Small businesses often fall victim to cyberattacks because they are less likely to have advanced security measures, making them easy targets.
See Also: How to Implement the Security Awareness Program for PCI Compliance
Given the threat of email-borne cybercrime, your employees must have a solid understanding of how email-based threats work and how they can be prevented. Employees should be trained on responding when they believe they have received a malicious or suspicious email.
Staff will reply in one of two ways if they receive a phishing email. They can open the file, infect their devices with malware, and potentially cause a large-scale breach attack on your company, or they can delete the file and forward it to the IT department.
The IT department can then choose to send an email or note to other employees warning them not to open such emails. If attackers send the email to other employees, they are less likely to be tricked into opening attachments.
See Also: Why Email Server Security Matters
Email protection can be improved with comprehensive cybersecurity awareness training. However, if an employee who receives a malicious email does not know how to differentiate a fraudulent email from a legitimate one, the risk of being hacked significantly increases.
Employees can learn how to recognize and report suspicious emails as part of their cybersecurity awareness training. Training should be revised regularly to keep up with changing scam strategies.
Other cybersecurity awareness tips to use in security awareness training are as follows:
- Make it clear how important it is to keep business and personal emails apart.
- Deter employees from checking business emails on their mobile phones.
- Encourage employees to update their email passwords regularly.
- Encourage employees to use complex, unique passwords.
2. Ensure Password Security
Our main line of protection against cybercrime and unauthorized access to our confidential data is passwords. But passwords are only as strong as we create them. There are several ways to keep passwords strong and secure.
You should implement a password policy for employees to follow to make sure they understand what creates a strong password and not inadvertently creating security vulnerabilities in your network.
The password policy should include the following as standard:
- Reset passwords regularly.
- Make sure passwords are unique and cannot be reused across multiple accounts.
- Make sure passwords do not contain general phrases or personal information.
- Make sure your passwords are at least eight characters long and contain both lowercase and uppercase letters, as well as symbols and numbers.
- Prevent password sharing.
- Store passwords securely.
Strong passwords are a critical best practice for email protection and play a vital role in protecting your email accounts. Enforcing a password policy can help you secure your password.
3. Develop a Cybersecurity Plan
The password policy should be implemented as part of a larger cybersecurity strategy. With a solid, well-developed cybersecurity plan, many of the threats and risks that lurk online can be avoided.
Be sure to prepare for email-borne threats while creating a cybersecurity strategy. Policies, guidelines, requirements, and recommendations for implementing and using all your company technologies, including email communication channels, should be included.
Creating a cybersecurity plan is very important because even the most successful corporate email security best practices will become obsolete if your company is vulnerable to cyber-attacks in other areas.
4. Use an Antivirus Solution
Many corporate antivirus solutions are equipped with mail filtering and scanning functions for files and websites. These features will help the organization proactively identify email-based threats and lower the risk of your devices and networks being hacked.
If possible, it is recommended that you set up your antivirus software to work with your mail relay. This way, your antivirus solution can scan business emails and filter malicious emails, helping prevent your employees from receiving them.
5. Apply Email Security Solutions
In addition to antivirus software, you should consider implementing other email security tools such as anti-malware and mail protection solutions. Corporate email security tools can help you detect and defend against targeted attacks by reducing human error risk leading to business email compromise.
An identity tracking tool is one of a kind email security solution that can be extremely useful for businesses. Identity tracking solutions can help prevent account inheritance, shorten response time with early alerts, notify you of available credentials, and monitor multiple domains.
6. Use endpoint email security solutions
Endpoint email security encompasses various tools and processes that prevent end users’ devices from being compromised by email attacks. Phishing emails, spam, and malware can all be used to target employees. If these malicious emails are opened, they can infect their devices and provide gateways for hackers to access the entire corporate network.
To combat malicious emails, organizations should install endpoint email security software along with antivirus tools. These can stop compromised systems from sending outbound spam by filtering and blocking malware or spam from suspicious senders and IP addresses.
In particular, endpoint security software can verify whether a device meets security policies before allowing it access to an organization’s network. Access to remote devices that have not updated their operating system, turned off the firewall, or have other specially recognized vulnerabilities will be denied to mitigate external threats to the network.
EmailMalicious actors also use email to perform zero-day attacks that exploit previously unknown flaws in software, hardware, or firmware. An essential countermeasure against this requires your IT team to upgrade and patch all endpoints regularly.
While this measure will not wholly stop zero-day attacks, it will reduce their chances of success or at least save you more time until the corresponding zero-day patch is available.
Another critical component of endpoint protection involves enforcing enterprise-wide policies regarding core password and corporate email security best practices. For example, you can instruct employees to:
- Avoid storing passwords in paper notes and public places.
- Avoid copying old passwords or passwords created on other sites.
- Create strong passwords that contain (@) characters instead of alphanumeric letters (a).
- Use passwords that strangers cannot guess.
7. Protect your email content with encryption
All email content and attachments must be encrypted in transit and at rest in the inbox to secure the email content fully.
Popular email platforms like Gmail and Outlook frequently lack enterprise-grade email encryption, making it difficult for businesses to protect themselves against all cyber threats completely. To the extent that cloud email platforms support encryption, they will only work if both the sender and the recipients have specific extensions enabled.
See Also: Public Key Cryptography and PGP Fundamentals
Third-party plug-in encryption services can close these corporate email vulnerabilities. However, bear in mind that some of these encryption services will make the user experience more challenging.
Any encryption technique is only valid if users can integrate it into their daily routine. Therefore, before making your final choice, carefully weigh your options by testing the trial versions.
Unauthorized access to sensitive information exchanged via email can also be prevented with document protection solutions. These solutions function by allowing you to monitor who has access to your records, including who can view, print, and download them. After you’ve sent your emails, you may also revoke the recipient’s access.
Expiry settings, watermarks, screen capture security, and monitoring also give you more control over keeping your confidential documents safe and secure. These important document security features should be part of any third-party encryption service you choose.
8. Protect your email server
Email services can be hacked, and servers used to store and send email can be compromised. Spam and DDoS attacks on these servers can interrupt standard email transmission and processing. Also, hackers can send spam emails from your server, damaging your reputation and making you blacklisted.
Therefore, it is essential to protect your email servers. Guide your IT team to implement robust email server protection techniques, starting with:
- Restrict the mail relay parameter by specifying a list of domains and IP addresses where your mail can be forwarded securely.
- To reduce the risk of spam and DDoS attacks, limit the number of connections.
- Verify the sender with a reverse DNS lookup before accepting incoming messages.
- Use content filtering to combat spammers from accessing your server.
It is essential to work with your IT team to provide all the necessary information to secure your email servers. Separating real genuine emails from spam, phishing attacks, and other threats early can help keep your intellectual property and confidential company information safe.
9. Prevent data leakage and breaches
Confidential documents often share specific properties. They may have similar keywords, data types, or rules intelligently used to identify these documents. Your organization can prevent such sensitive data from leaking in emails by filtering, blocking, or censoring based on keywords, phrases, and rules.
For example, your IT team can block all outgoing emails containing personal information such as social security numbers, credit card information, and files containing the keyword “confidential” or “internal use only.” It is also a good rule to use encryption to protect outgoing data while filtering incoming emails to block malware, viruses, and phishing threats.
Data loss prevention (DLP) tools can be implemented to prevent sensitive information from spreading outside your organization by alerting your IT administrator of data access policy violations. DLP allows your IT team to proactively respond to problems after a data leak occurs rather than trying to repair the damage.
Predictive technologies such as machine learning (ML) and artificial intelligence (AI) are increasingly used for real-time monitoring to detect unusual data patterns that can identify and prevent data breaches.
Without effective Data loss prevention (DLP) tools, your organization runs the risk of unwanted disclosure of customer data that could lead to identity theft, monetary fraud, and loss of your business reputation.
10. Back up important files
While implementing an effective corporate email security strategy dramatically reduces an organization’s exposure to a cyberattack, no strategy or solution is entirely foolproof. Businesses must back up sensitive files regularly and automatically to minimize the potential for loss and destruction in the event of a ransomware attack.
Be aware that advanced ransomware variants can be idle for weeks until they are triggered, potentially destroying backups. Threat actors are also getting more intelligent and attacking backups to prevent recovery.
However, there are several ways businesses can protect their backups from ransomware:
- Support backups with additional copies held in multiple locations.
- Isolate backups. The more barriers between an infected system and its backups, the more difficult it will be for ransomware to attack those backups.
- Test backups frequently. Regularly perform restoring exercises to identify issues or vulnerabilities.
11. Protect email accounts with sender authentication
Spammers can easily spoof your email address. If you want to prevent email spamming from your account and maintain the reputation of being a legitimate business in the industry, you must authenticate your email.
Sender authentication uses cryptographic standards and protocols to verify that an email is from the individual it claims to be, avoid phishing attacks, and secure email accounts from other threats, including email fraud.
The most widely used email authentication standards that make this verification possible are SPF, DKIM, and DMARC.
DKIM stands for “Mail Identified by Domain Keys.” Applying your digital signature to all outgoing email headers prevents your company from being used for email fraud. A custom domain key encrypts all email headers sent from your domain and adds a public version of this key to the domain’s DNS (Domain name system) server.
The recipient can then retrieve this key from the DNS records and decrypt the email header. Anyone receiving an email from your address should be sure that it was sent from your domain and was not tampered with in transit.
DMARC stands for ‘Domain-Based Message Authentication, Reporting, and Compliance. The DMARC policy allows actual senders to show in their messages that their emails are protected by DKIM or SPF (Sender Policy Framework). They can indicate to recipients if the email fails DMARC authentication.
DMARC is the most helpful way to handle email spoofing compared to other methods. This is because it allows email recipients to recognize a message from your email address and provides a way for recipients to report if they have received any suspicious email from your name/domain.
DMARC combines the mechanisms used in SPF and DKIM to allow domain owners to declare how they would like emails from this domain to be handled if they fail an authorization test.
Sender authentication should ideally be used as part of a more comprehensive email security solution. As with any security aspect, defense in depth is the key to adequate protection, and sender authentication is no exception. Look for a solution that uses SPF, DKIM, and DMARC to analyze and track the sender’s reputation.
12. Create email blacklists and whitelists
A valid list of banned email addresses (blacklist) helps prevent known spammers or cyber threats from reaching your inbox. Whether you’re doing it in-house or using third-party blacklist authority, make sure it’s done. You can create the list by domain name, email address, and IP address/range.
The list of email addresses allowed through your whitelist or filters and your server is almost equally important. The whitelist can also be maintained via domain, email address, and IP address/range.
13. Use S/MIME protocol for data encryption and email signing
You can use S/MIME, an advanced email security best practice, or the secure internet mail extension (S/MIME) protocol to help prove your identity to the recipients of your email while also helping to protect their integrity data.
The S/MIME protocol is an email signing protocol that enhances email security by:
- Creates a timestamped digital signature to verify the identity of the sender to the recipient.
- Encrypt and decrypt the content of emails to provide data protection at rest and in transit.
- Facilitates secure sharing of documents across networks.
By uploading an S/MIME certificate, you demonstrate your commitment to data security. While pre-installing these certificates, which require manual setup on each device individually, is cumbersome, some modern certificate management solutions now automate and simplify the process.
14. Use encrypted communication protocol
Email is inherently insecure because emails work over the Unencrypted Simple Mail Transfer Protocol (SMTP). So any email you send can go through several SMTP relay servers before it reaches its proper destination.
See Also: What You Need to Know About Encrypted Communication
The problem is that if your message is not encrypted and enters a malicious server, the content of your information is at risk of being compromised. Fortunately, you can prevent this by using Transport Level Security (TLS), which encrypts all your email messages and ensures that the intended recipient can only read the content.
15. Take precautions against email fraud
Email scams are one of the favorite tricks of cybercriminals. If you fall victim to email fraud attacks, you or your business can lose its reputation without you even realizing it. Email spoofing is also called BEC or Business Email Settlement.
In this case, hackers impersonate your corporate identity to steal confidential information and sensitive company data or make fraudulent money transfers.
Most email scams use one technique like click trap, subject lines, and targeting several employees.
Whatever the case may be, your compromised email will be reported as spam or fraud, which will be a severe problem for the company’s reputation. Access an email security provider to protect yourself against email fraud and help you evaluate and fix such threats.
16. Use two-factor authentication
Hackers are known to guess passwords easily. However, two-factor authentication can prevent them from reaching your inbox.
Two-factor authentication will ask you for two pieces of personally identifiable information before successfully signing in to your account. Usually, this second verification is a temporary password sent to your mobile device via text message.
Since only you have access to your phone, no one else will be able to access your inbox. If anyone tries to break into your email, you will stay tuned and receive a notification.
Final Thoughts on Email Security
Email security is a versatile process of protecting email data and sensitive information using defense techniques and technology. It all starts with training and knowing what to do, and businesses need to keep their data private to the account owner.
In today’s busy world, email is essential for communication. But what if something goes wrong and your security is compromised? Viruses, phishing scams, and information breaches are not uncommon and have high costs.
See Also: PCI DSS Data Classification Requirements
Email security can often go astray, but taking action to avoid a messy situation is not complicated. It is essential to be aware of the risks of using email and how to proactively protect against them to ensure your data does not fall into the wrong hands.
Your business doesn’t have to compromise seamless collaboration to communicate confidential business information securely. Since email is at the center of business communication for most organizations, ensuring this channel’s security is of paramount importance.
Applying corporate email security best practices can help prevent attacks and data breaches. This is key to building trust in your organization’s operations, employees, and customers.
Employees can help ensure that their work email accounts are safe from email-borne threats by applying the corporate email security best practices listed in this guide.
None of the email security best practices mentioned above are designed to work alone. To ensure strong email security, you must implement multiple email security best practices to mitigate potential vulnerabilities and threats.
