Before an email leaves the company network, it must pass through a secure gateway. This helps prevent sensitive data and malware from going through the organization.
Email gateways can be deployed on-site or as a cloud service, using services like malware protection, content filtering, a centralized admin dashboard, and configurable automated reports.
Incoming Emails
Email gateways are the first defense against cyber threats entering and leaving an organization. They operate on the network, not the end-user devices, to scan incoming emails for malicious content and prevent harmful emails from reaching your employees’ inboxes or their devices. Those are the basics of how email gateway works, so let’s go deeper.
To detect and remove malware from incoming emails, SEGs utilize several techniques and tools, including spam filtering (using algorithms to quarantine or block email domains that have been known for sending spam) and content filtering (analyzing the content of an incoming email using scanning technologies like sandboxing, reputation analysis, and more). SEGs also scan outgoing emails to ensure no sensitive data is sent via email outside the organization’s network. This is a crucial step because, according to research, 9 out of 10 data breaches are caused by human error – which often involves sharing information with the wrong person or emailing files to external recipients.
SEGs scan all incoming and outgoing emails for the presence of viruses, malware, or malicious attachments using a variety of techniques and tools, including signature detection, malware scanning, heuristics, and more. They also scan outgoing emails for sensitive data and images using heuristics, sandboxing, and URL rewriting to prevent confidential or proprietary information from falling into the wrong hands. Lastly, SEGs provide system administrators with centralized controls and automated and configurable reports to help manage their email security networks.
Spam Filtering
Billions of emails are sent and received daily, from professional correspondence between organizations to personal email exchanges. These emails contain text, videos, pictures, and documents. A secure gateway is an email server that handles these emails in a protected form so that they can reach their intended recipients without exposing them to potential threats or phishing attempts.
Spam filters are one of the main features a secure email gateway offers to protect an organization’s email infrastructure. These tools can block spam emails by analyzing the content and identifying patterns of malicious behaviors. They also use blocklists of known spam senders and domains to prevent incoming emails from reaching the end-user’s inbox.
A reputable email gateway is also capable of detecting and preventing phishing attacks. It compares the emails against a database to identify known phishing patterns and characteristics, such as suspicious URLs or hidden malware. It also includes anti-ransomware capabilities, which stop malicious files from being downloaded or opened in the organization’s network and deliver their payloads to the system.
Most advanced secure email gateway solutions also include data loss prevention (DLP) capabilities that prevent sensitive information from leaving the organization’s email network. This can be done by analyzing the contents of outgoing emails and their attachments for data leaks and encrypting them before sending them. This helps to comply with regulations like UK GDPR and other industry-specific compliance requirements.
Content Filtering
Emails can quickly get bloated with spam, phishing attempts, and hidden malware. This can be especially problematic for businesses. Emails can contain confidential data, login information, accounting details, and legal documents. An SEG can prevent hackers from accessing private data or launching denial-of-service attacks by filtering for malicious email content.
To do this, SEGs analyze the contents of incoming emails and identify patterns and common elements of malicious messages, such as suspicious keywords and links that could take the recipient to dangerous websites. They also compare the email’s source against a list of known spam senders and domains. If the SEG detects spam or other malicious content, it will block or quarantine the email for further inspection by the system administrator.
SEGs can also scan outgoing emails to ensure no sensitive or confidential data is included before they leave the organization’s network. This helps companies comply with regulatory requirements, such as UK GDPR.
If the SEG detects sensitive or confidential data in an outgoing email, it will encrypt that message before sending it to the intended recipient. This is a great way to keep sensitive data safe if an employee’s device falls into the wrong hands. This functionality is often available through an email gateway integrated into a business’s unified communications platform.
With the rise of online platforms, account takeover fraud detection has become a priority for many companies. Cybercriminals often try to gain unauthorized access to users’ accounts, making it vital for platforms to have measures in place to detect and prevent these intrusions.
Encryption
Emails are the #1 cyber threat target for attackers, and they’re not just targeting individuals. Still, also businesses and organizations. Using an SEG allows a company to block unwanted emails and protect its entire network from threats, including phishing attacks and hidden malware.
In addition to detecting and preventing spam and phishing, SEGs can scan all outgoing emails for sensitive content and prevent confidential or proprietary information from leaving the company’s network. This is especially important for regulated industries that comply with data protection regulations, such as the UK’s GDPR.
To do this, an SEG inserts itself into the flow of all email traffic by updating the organization’s MX record to point to it. Once it receives an incoming message, it undergoes DLP, AV, and server-side signature checks before being encrypted with Key A. The message will only be decrypted once it gets to the recipient’s inbox, and even if a threat actor intercepted it, they would only be able to see its contents if they have both keys, which would be impossible to acquire.
Organizations that deploy an on-premises SEG will be responsible for purchasing, maintaining, and continually updating the hardware. On the other hand, those that choose a cloud-based solution will not have to worry about this, as it is the security vendor’s responsibility to maintain service availability.
