10 pfSense Firewall Rules Best Practices (2023)

FAQs

Which default _____ strategy for firewall rules is the best practice? ›

There are two basic philosophies in computer security related to access control: default allow and default deny. A default deny strategy for firewall rules is the best practice.

Each firewall rule is composed of six parts, which together define conditions under which a given network request is permitted or denied. These components are action, direction, target, source/destination, protocol and ports, and priority.

Explanation. The four techniques used by firewalls to control access and enforce a security policy are Service control, Direction control, User control and Behavior control.

Where most firewall rules only inspect headers at layer 3 (IP address), 4 (Transport), and 5 (Port), a layer 7 rule inspects the payload of packets to match against known traffic types.

Identification of all Internet Service Providers (ISP) and Virtual Private Networks (VPN) All relevant firewall vendor information including OS version, latest patches and default configuration. Understanding all the key servers and information repositories in the network and the value of each.

Creating a Firewall Rule​

Navigate to the Firewal `> Rules on pfSense web GUI. Select the interface that you want to define a rule, such as WAN, LAN, VLAN10 or GUESTNET, etc. This will list the existing firewall rules on the selected interface.

Firewall rules have a priority order that determines the order in which the rules are applied to network traffic. Firewall rules are shown as a list on the Rules page. The rules are applied from top to bottom, and the first rule that matches the traffic overrides all the other rules below.

What ports should always be closed? ›

For a very simple example, you might have a rule that says, “Allow any traffic from IP address X to port Y.” When a packet arrives at the firewall, the firewall reads its source and destination. If the packet's source is X and its destination Y, it passes through.

In pfSense® software, rules on interface tabs are applied on a per-interface basis, always in the inbound direction on that interface. This means traffic initiated from hosts connected to the LAN is filtered using the LAN interface rules.

Functions of Firewall

Therefore, a firewall's primary function is to secure our network and information by controlling network traffic, preventing unwanted incoming network traffic, and validating access by assessing network traffic for malicious things such as hackers and malware.

Firewall Rules can take the following actions: Allow: Explicitly allows traffic that matches the rule to pass, and then implicitly denies everything else. Bypass: Allows traffic to bypass both firewall and Intrusion Prevention analysis.

There are two types of firewalls based on what they protect: network-based and host-based. Network-based firewalls, which are frequently hardware, protect entire networks. Host-based firewalls, which are frequently software, protect individual devices known as hosts.

You can use two types of Firewall policies in Network Security Platform — advanced and classic. Functionally, these two types are similar. However, as the names might suggest, advanced Firewall policies provide you more options to filter traffic when compared to classic.

The maximum number of firewall rules that can be set in WFBS depends on the number of exceptions configured in one policy or rule. The maximum number of limitations that can be inserted in a policy or rule is 1024. Also, the number of exception rules configured in one policy may affect how many rules can get inserted.

What are the six 6 basic network security measures? ›

Layer 3 Firewall rules provide an administrator granular access control of outbound client traffic. With the MR series, outbound traffic refers to client traffic originating from the wireless network that is destined for the wired LAN or Internet.

Application layer or Layer 7 DDoS attacks are among the most sophisticated and powerful types of attacks that can be launched against a website or application. These attacks work by overwhelming the target with requests that appear to come from genuine users, thereby preventing legitimate traffic from getting through.

L4 Firewalls or Layer 4 firewalls (i.e., session filtering firewalls): Ability to do this, plus adding the ability to actively track network connections and allow/deny traffic based on the state of these sessions (i.e., stateful packet inspection). sessions (i.e. stateful packet inspection).

Firewalls can also perform various functions, such as packet filtering, stateful inspection, proxy service, and deep packet inspection, to control and monitor the traffic between your network and the internet.

At its most basic, a firewall is essentially the barrier that sits between a private internal network and the public Internet. A firewall's main purpose is to allow non-threatening traffic in and to keep dangerous traffic out.

Floating Rules are a special type of advanced rule that can perform complicated actions not possible with rules on interface or group tabs. Floating rules can act on multiple interfaces in the inbound, outbound, or both directions.

Stateful Filtering. pfSense software is a stateful firewall, which means it remembers information about connections flowing through the firewall so that it can automatically allow reply traffic.

OPNsense is a free, open-source firewall and routing platform based on HardenedBSD. It was created as a fork of pfSense, aiming to provide a more modern and secure alternative.

Does firewall rule order matter? ›

As mentioned earlier, firewall rules are evaluated on a top-down basis. The first rule that matches a packet is executed, and the rest are skipped. It is important to consider the order of firewall rules. Often specific rules will proceed more general rules.

Ports 80, 443, 8080 and 8443 (HTTP and HTTPS)

HTTP and HTTPS are the hottest protocols on the internet, so they're often targeted by attackers. They're especially vulnerable to cross-site scripting, SQL injections, cross-site request forgeries and DDoS attacks.

Commonly hacked TCP port numbers include port 21 (FTP), port 22 (SSH), port 23 (Telnet), port 25 (Simple Mail Transfer Protocol or SMTP), port 110 (POP3), and port 443 (HTTP and Hypertext Transfer Protocol Secure or HTTPS).

Hackers do not have a preference for which ports they use. They will use port scans to identify ports to open. Commonly targeted ports include widely used programs by network teams for remote administration, web applications, file transfer services, conferencing software and common remote connectivity.

Implicit deny is usually the last rule by default in current firewalls, however an administrator may put an Explicit deny rule last so that they can log that traffic as well.

By default, the firewall prevents all traffic from a lower security zone to a higher security zone (commonly known as Inbound) and allows all traffic from a higher security zone to a lower security zone (commonly known as Outbound).

The Firewall Filtering policy has one default rule, which handles all the traffic that does not match any user-defined rule with a higher rule order. The default rule always maintains the lowest precedence and cannot be deleted. Only admins with the super admin role can modify the default rule.

What is default allow firewall policy? ›

A firewall policy is a filter that allows or denies traffic based on a matching tuple: source address, destination address, and service. By default, firewall policy rules are stateful: if client-to-server traffic is allowed, the session is maintained in a state table, and the response traffic is allowed.

3. What is the best practice in the firewall domain environment? Explanation: All live servers or workstations are kept in a separate zone than inside and outside to enhance protection. 4.

They've since become the foundation of network security in the client-server model -- the central architecture of modern computing. Overall, firewalls play an important role in preventing cyber attacks, protecting sensitive data, and maintaining the privacy and security of computer systems and networks.

Firewall rule management is the process of periodically reviewing and optimizing firewall rules. This process involves the following: Analyzing rule anomalies that affect the performance of the firewall. Reordering existing rules to improve rule performance.

Firewall rules are stored under the Software\Policies\Microsoft\WindowsFirewall\FirewallRules key. Each value under the key is a firewall rule.

Click the Start button, then type Windows Firewall in the Search box. Click Windows Firewall, and then click Allow a program or feature through Windows Firewall. Click the Change settings button. If a User Account Control window appears, click Yes, or enter your user name and password, then click OK.

Definition(s): To block all inbound and outbound traffic that has not been expressly permitted by firewall policy.

Idle timeout is the maximum length of time that a TCP connection can stay active when no traffic is sent through the connection. The default global idle timeout for all traffic is 3600 seconds (1 hour).