Your firewall rulebase can feel like that one drawer in your house where you toss all life’s miscellany. As you expanded your network environment, you may have collected rules from traditional firewalls, next-generation firewalls (NGFW), SD-WAN, and SASE. Like dropping an extra rubber band in a kitchen drawer, you drop new rules across your networks when adding new firewall devices or software. As you add new vendors and their proprietary naming conventions, you increase the number of rules while decreasing your visibility into network topology.
Similar to how you side eye that kitchen drawer, you might currently be glancing askance at your firewall rulebase. You know that you need to clean up and organize everything, but the process is time consuming and tedious. As you focus on more important, strategic tasks, the rulebase continues to grow until the rule bloat starts impacting your network performance and security.
Leveraging automation enables you to implement these five firewall rule cleanup best practices so you can clear out that digital junk drawer while ensuring continued productivity.
Why Should You Cleanup Your Firewall Rule Base?
When the kitchen drawer no longer closes all the way and people start walking into it, you know it’s time to empty it out. A cluttered firewall rule base similarly gets in your users’ way because it degrades firewall performance and increases security risks.
Enhanced Performance and Efficiency
Optimizing firewall rules significantly boosts firewall and network performance by processing traffic more efficiently. Eliminating redundant or outdated rules improves network throughput to minimise latency, promoting faster data and more reliably data transmission.
Improved Security Posture
A well-maintained firewall rule base minimizes the attack surface, reducing the risk of unauthorized access and data breaches. Regularly reviewing and optimizing firewall policies can protect against potential vulnerabilities, closing security gaps presented by redundant or unused firewall rules.
Simplified Firewall Management
Creating a standardized view of all firewall vendors and their rules reduces clutter to mitigate potential risks arising from disabled rules and duplicate objects. Creating a cohesive view of all firewall policies and rules enables administrators to respond to violations faster.
Regulatory Compliance and Auditing
Regular firewall rule optimization and documentation demonstrates a commitment to maintaining a secure and compliant network. Firewall rule cleanup improves compliance reporting to mitigate compliance violation risk, especially for mandates and frameworks like:
- NERC CIP
- ISO 27001
- PCI DSS
- NIST 800-53
- GDPR
5 Best Practices for Rule Cleanup
If your firewall rule base looks like the network version of that doom corner with a pile of clothing, then you should consider the following five best practices to help you get started.
Simplify Rules
Streamlining firewall rules involves merging redundant rules to reduce clutter and configuration disputes that could compromise security. Some examples of simplifying rules include:
- Employing clear, common naming conventions
- Keeping rule sections concise
You want to simplify your rules so you can understand how users interact with resources and data transmitted across network segments.
Tufin’s Unified Security Policies (USPs) allow you to centrally manage security policies, even in the face of long and complex rulebases. When you define the requirements for your USPs, the matrix defines the traffic your compliance requirements allow between your Network Zones, then monitors actual use and measures it against your policies to identify potential violations.
By utilizing Tufin’s USP’s, you can comprehensive insights into your overarching network security posture. Our Topology Intelligence collects interface information and routing tables so you can make informed decisions about your network security. These capabilities effectively streamline your insights by providing visualizations for how people use your networks.
Analyze Rule Usage
Rules are like the items sitting in that kitchen drawer where you might use the scissors regularly but never take out the rubber bands. Analyzing rule usage by reviewing traffic logs can tell you how people are actually using networks and access. With insight into the realities of your network, you can more easily identify:
- Unused rules and objects
- Overly permissive rules
- Shadow rules
Tufin’s Rule and Object Usage Report calculates the logged network traffic passed or blocked for each rule or object to display statistics for most-used, least-used, and unused rules and objects. You can use this report to:
- Identify rules that should be considered for removal
- Identify heavily used rules that can be moved up in the rule base
- Analyze objects that may be candidates for removal
Some maintenance tasks you can schedule with Tufin include:
- Database optimization: automatically optimizing the database
- Rule usage statistics: collecting data from devices lofs that shows rules with traffic hits
- Object usage statistics: collecting data from devices logs that show objects with traffic hits
Remove Duplicate and Unused Objects
Duplicate objects within a firewall configuration can complicate management and increase the likelihood of misconfigurations. Duplicate objects use the same definition but different names, an issue common in network environments that have multiple firewall vendors. Duplicate objects can create problems like:
- Misuse in a policy rule
- Misconfigurations or vulnerabilities leading to a security incident
- Connectivity disruption
To streamline this process, you can use Tufin’s Cleanup Browser to get the details about the different policies and rules that you can optimize. The Cleanup Browser supports the following identifications:
- Duplicate network objects: hosts with the same IP address, networks with the same IP address and netmask, and IP address ranges with the same start and end addresses
- Duplicate services: services containing the same values for protocol, destination port, source port, timeout setting
After you identify duplicate objects, you can use Tufin’s automated workflows to:
- Engage in an impact analysis to identify where the servers or network objects are used in firewall rules across all firewalls
- Change firewalls rules to decommission the servers or network objects from all firewall rules
- Verify removal from all firewall rules
Decommission Shadowed Rules
Firewalls never process shadowed rules because prior rules match the incoming traffic, risking unintentional security breaches by overriding critical mechanisms. Since the firewall doesn’t execute these rules in normal operations, removing them carries a low risk while significantly improving network security and performance.
When using Tufin’s Rule Viewer, you can easily identify fully shadowed rules and gain insight into the details like:
- Permissiveness
- Last modification
- Compliance or policy violation risk
While the Rule Viewer provides insights, the Cleanup Browser streamlines the rule decommissioning process. Since all cleanups are defined with a name, severity, and description, you can engage in meaningful review to ensure that you want to remove the rule.
Tighten Overly Permissive Rules
By focusing on rules safeguarding critical applications and sensitive data, your rulebase streamlines access to essential services while reducing the attack surface. In some cases, rules may be overly permissive, creating an unauthorized access risk.
Using traffic data about actual rule usage, Tufin can identify how widely a rule is defined, indicating it as low, medium, or high levels of permissiveness. To streamline your security and compliance capabilities, our Automatic Policy Generator (APG) automatically tightens these permissive rules.
Tufin: Automate Processes for Streamlining and Optimizing Firewall Configurations
Tufin’s suite of solutions enables you to continuously and painlessly cleanup your firewall rules. When you use Tufin, you can align rules and policies to business objectives by identifying and reviewing the need for unused or low-use rules. By determining actual rule usage with our APGs, you can enforce the principle of least privilege consistently across all network devices, enhancing both your network security and compliance.
With the ability to engage in regular rule cleanup and firewall optimization, you can reduce audit costs, improve performance, and mitigate cyber risks. Tufin’s workflows ensure that all network changes are compliant so that you can automate and document security policy enforcement and exceptions, as required by compliance mandates and framework.
To see how Tufin can improve your network security and performance, contact us today for a demo.
- Home
- Blog
- Continuous Compliance & Audit
- 5 Firewall Rule Cleanup Best Practices
