OPNsense

Disable Logging into OPNsense as the Root User

Disable Logging into OPNsense as the Root User

Allowing root user logins is not normally a good idea...

After installing OPNsense, the default login is the root user. Logging in as the root user is generally not advised because the root user has full access to files and processes. Linux users, for instance, are asked to create a separate user account upon installation. The user can then use the sudo command to elevate privileges to perform administrative tasks. If the user's account is compromised, in theory the root account is still protected (assuming there is no privilege escalation vulnerability being exploited or the password has been discovered).
Inadvertently Opened SSH Remote Access

Inadvertently Opened SSH Remote Access

Be careful when using aliases because you could expose unnecessary services to the world...

In my network, I created an alias for all of the ports I have open on my server so that I can create firewall rules to allow several of my VLANs to access the services hosted on my server. The benefit of creating an alias is that I do not need to create 4 separate firewall rules to open 4 different ports to my server and then repeat this process for each VLAN I need to allow access (yes, you could use floating rules or rule groups depending on the order you need rules to be processed).
A Feature Comparison of the OPNsense Plugin Sensei by Sunny Valley Networks

A Feature Comparison of the OPNsense Plugin Sensei by Sunny Valley Networks

What is Sensei and what is the difference between the Free Edition and Home Edition?

Sunny Valley Networks is a startup company that has partnered with Deciso, the creators of OPNsense, to create a plugin called Sensei which adds deep packet inspection and more to OPNsense. These features add greater visibility into your network. Sensei also has built-in cloud threat intelligence that can be used to block web/application access and to prevent known malware attacks. This post will focus on the features of Sensei and the differences between the Free Edition and the Home Edition.
OPNsense Firewall Rule "Cheat Sheet"

OPNsense Firewall Rule "Cheat Sheet"

A quick guide to creating firewall rules in various situations

When looking up information on how to write firewall rules in OPNsense, you may be looking for specific examples on how to block or allow certain types of network traffic rather than how to write firewall rules in general. This is especially true once you become more experienced and comfortable with writing rules. I thought it would be a good idea to consolidate a variety of scenarios into a single how-to that could be used as a quick reference guide.
How to Protect Against the Cable Haunt Vulnerability Using OPNsense

How to Protect Against the Cable Haunt Vulnerability Using OPNsense

Is your modem vulnerable to Cable Haunt and your ISP has not provided a firmware update? Take matters into your own hands!

Cable Haunt is a recent vulnerability that has been found in over 200 million cable modems in Europe and likely many more in other countries as well. Many modern modems use similar Broadcom chipsets and used the same reference firmware which contained the vulnerability. Because of this, the impact of this vulnerability is much greater than it would have been otherwise. Software running in many (probably nearly all) consumer modems have not implemented best practices for security.