Microsoft Exchange Server is, without a doubt, a powerhouse when it comes to the email exchange server preferred by most businesses.
Large organizations seem to trust established brands in facilitating their day to day operations, and Microsoft is indeed an established company as they come.
However, popularity also comes with increased attention, some of which may arise from unwanted quarters like cybercriminals seeking to manipulate your server to conduct fishy business.
With activities like spamming, spoofing, and phishing on the rise in this modern-day, all admins now need to learn best practices to keep their Exchange Server safe.
Below we look at some key points to consider:
1. Implement relay restrictions
You will be using your Exchange Server to send and receive relevant emails for your business. You can also consider using Comcast email via POP, one of the oldest internet message access protocols.
As such, you need a clean reputation that your server is not associated with spam whatsoever and that all your clients and associates can open any emails you send them without fear or suspicion.
However, should you choose not to implement relay restrictions, your mail server becomes an open relay which is like literally awarding lottery tickets to spammers.
Anyone will be able to relay email through your server and spammers can put you in trouble by hiding their IP address such that all their spamming messages will appear to originate from your server.
When organizations realize that your server is being used to send spam, your Exchange Server will end up being blacklisted landing a big blow to your business.
Additionally, spammers make use of your resources like disk space, internet bandwidth, and CPU time, thus affecting the intended usage for your business. Implementing relay restrictions is, therefore, paramount.
2. Always keep your Exchange Server updated
Just like your car deserves regular maintenance and servicing, your Exchange Server too must always be kept up to date.
Microsoft occasionally releases patches that can rectify known security threats and bugs in both the Windows operating system and Exchange Server. Although some administrators are wary of new patches when they become available as they are not sure if the patches are buggy or not.
It is important to note that hackers are always on the lookout for the time when Microsoft releases new patches exposing existing security vulnerabilities. They will then hurriedly exploit this information to attack unpatched servers.
The best thing is to have a patch test lab so that you analyze a new patch immediately once it is released. If no bugs are found be quick to update your Exchange Server so that hackers don’t beat, you to it.
3. Have enhanced virus protection
Although regular antivirus software can protect domain controllers and file servers against viruses, the game changes a bit when you consider the protection needs for an Exchange Server.
Your mail server will be transporting files regularly in and out of your entire organization, and therefore you need to consider protection on different levels. To start with, file-level antivirus software is essential to monitor your file system closely and remove any existing viruses.
Next, you will need an Exchange Server level antivirus software that can track your Exchange database and get rid of any infected files without corrupting the system.
You can additionally have workstation and gateway levels antivirus products to make sure that you seal all loopholes that viruses may use to creep into your organization.
4. Use Exchange Server SSL certificates
An Exchange SSL server certificate, also known as a UCC (Unified Communications Certificates) SSL certificate is used to secure the Exchange Server communication with powerful encryption distinctively.
There are three types of SSL certificates that you can use to secure communications on your Microsoft Exchange Server.
The first is a self-sign certificate that you can create easily by yourself. Secondly, you can use a Windows Public Key Infrastructure (PKI) certificate. Thirdly, there are Trusted CA Authority SSL certificates that Microsoft recommends to all its customers seeking maximum protection.
Some reputable SSL certificates you can consider for your setup include Multi-domain SSL, EV Multi-domain SSL, Multi-domain Wildcard SSL, and the Multi-domain UCC SSL certificates.
5. Take advantage of the Edge Transport Server
The Edge Transport Server is a full-fledged Exchange server that offers numerous benefits to your organization.
First, it sets up a filtering mechanism at the network parameter blocking any viruses and spam before they can hit the hub transport.
Secondly, it keeps the memory of all recipients that have mailboxes on your server. This helps in blocking spam emails, preserving significant server resources, and even preventing denial of service attacks on your Exchange Server.
6. Limit administrative access
Most times, when large corporations have fallen victim to malicious attacks, there’s usually an inside job involved where either someone slacked in their job, or someone intentionally sabotaged your organization internally.
To curb this menace, limit administrative access on your Microsoft Exchange Server to an absolute minimum to ensure that you always stay on your guard.
7. Protect against DDoS attack
An IT admin should hire a DDoS attack mitigation vendor as well, admin can use the “Set-Transport Server cmdlet” on the exchange server to change the rates of message processing, rates of SMTP connections, and SMTP session time out values.
Moreover, the admin can apply “Set-Receive Connector cmdlet” to configure inactive timeouts, multiple connections, and SMTP connection errors.
8. Zero-day vulnerability
Antimalware defenses can detect a zero-day vulnerability and stops ‘helper’ software (RAT) that allows hackers to enter a compromised server.
Moreover, the admin can reduce the use of multiple applications, fix server vulnerabilities by applying patches, choose a Host Intrusion protection system, and use of firewall cleverly.
9. Use of reverse proxy
When you enable OWA service externally for users, you should use a reverse proxy. A reverse proxy decides whether to accept the user’s connection or not.
You can use Apache, Forefront, Squid, or hardware devices for reverse proxy. These proxies can stop hacking attempts and allows inside tools with granular level decisions.
The reverse proxy makes a different decision for the internal organization based on different solutions.
Conclusion
Moreover, you can use different tools like MBSA, security configuration wizard, EBPA. Email is a basic need for all businesses, and such an Exchange Server is an essential tool in the running of your organization.
With so many hackers and spammers on the loose seeking to siphon your crucial server resources and sabotage your company operations, it is essential to have necessary measures put in place like making use of UCC SSL certificates.
Make sure your Exchange Server remains up to date, and you will never have to lose any sleep about hacker attacks.
The Ideas Plus Business Editorial Team is led by Adeyemi Adetilewa, a Digital Marketing Consultant. If you’re interested in writing for Ideas Plus Business, read this article first.
