A Firewall Configuration Checklist to Streamline Audit Processes

Last updated August 22nd, 2024 by Erez Tadmor

Firewall configurations act as a network security defense against cyberattacks. By defining what traffic is allowed and blocked traffic, you gain control over who accesses your digital assets and what access they have. However, as your business needs change and your networks grow, manually maintaining secure firewall configurations across multiple providers becomes unwieldy.

Whether you are preparing for a third-party security audit or doing an internal firewall review, having a firewall configuration checklist can help you improve your network security and achieve desired compliance outcomes.

Why Do Firewall Configurations Matter?

Firewall configurations secure your network against unauthorized access by defining the legitimate traffic allowed in and out of the system. By screening traffic based on established security policies, a properly configured firewall mitigates the risk that malicious actors will exploit vulnerabilities.

Additionally, firewall configurations enable you to:

Identify network traffic patterns and anomalies indicating potential security threats

Comply with cybersecurity and data protection regulations and industry standards like PCI DSS, HIPAA, SOX, ISO, and GDPR

Gather Documents and Review Existing Firewall Policies

Whether adding new firewalls to your network or preparing for a firewall audit, you need the documentation that gives you insight into current configurations. For example, you should gather:

Network topology diagrams: showing network segmentation, DMZs, and data flows

Inbound rules: permitted incoming connections, services, and data to mitigate security risks like unauthorized access or malware

Outbound rules: permitted outgoing connections or data transmission to mitigate risky communications

Firewall rule order: specific rules placed before general rules with exceptions clearly defined and strategically ordered

When reviewing your inbound and outbound firewall rule base, you should consider the following best practices:

Place rules blocking malicious traffic at the top of the firewall rule base

Allow common services near the top to prevent accidentally blocking them

Use group objects to simplify security policy creation and reduce firewall rule base size

Review User Access Controls

Firewall rules governing user access define who connects to your networks and how they access resources. Some best practices include:

Securing firewall administrators’ accounts with multi-factor authentication

Enforcing remote access secure protocols, like secure shell (SSH) to encrypt data

Segmenting file transfer protocol (FTP) servers into separate subnets to reduce the attack surface

Ensuring remote users authenticate using a virtual private network (VPN)

Ensuring NAT configurations have appropriate source and destination IP addresses to protect internal networks

Implementing and enforcing the principle of least privilege with role-based access controls (RBAC)

Review Change Management Processes

For robust network security, you may have various firewall vendors and layers. While this improves cybersecurity, it can make change management processes more challenging. Some considerations include:

Assigning responsibility for approvals

Engaging in a risk assessment prior to implementing changes

Recording approvals before implementing firewall changes

Backing up existing firewall configurations before implementing firewall changes

Maintain Secure Software, Firmware, and Rule Configurations

Firewall management includes identifying and remediating vulnerabilities across various providers’ technologies. As part of improving network security, you should:

Scan devices, like routers, to identify known vulnerabilities in firmware and operating systems

Prioritize remediation actions using multiple vulnerability assessment measures including the Common Vulnerability Scoring System (CVSS)

Review rules governing access to and from assets and underlying services that can expose the vulnerability

Review connectivity requests before granting access to assets with known security vulnerabilities

Engage in penetration testing to identify weaknesses in firewall security

Optimize the Firewall Rule Base

As your networks grow, firewall rules can become inefficient, reducing security and performance. Firewall configuration analysis, cleanup, and optimization evaluate security policies to balance security and connectivity needs. When optimizing your firewall rules, you should:

Review rule interactions for correct prioritization

Identify and combine similar rules to streamline the firewall rule base

Review for shadow rules, general rules placed closer to the top of the firewall rule base that apply a different action or inspection than intended

Identify and decommission unused, low-use, or outdated firewall rules

Identify heavily used rules and reorder them accordingly

Document business reasons for maintaining low-use rules and security policy exceptions

Tufin: Automation that Streamlines Firewall Management

Tufin’s orchestration suite enables you to gain end-to-end visibility using vendor-agnostic Unified Security Policies for maintaining consistency across various firewall providers. Our solution integrates with firewall and network partners including Cisco, Palo Alto, Check Point, and Fortinet enabling you to create the layered network security defense that your organization needs while reducing the time your teams spend managing diverse rule sets.

Our change management workflows automate time-consuming processes, including real-time network risk and security policy violation detection. Tufin automatically checks for security policy violations with every access change and presents path analysis scenarios so you can proactively avoid risk. By centrally defining your policies in Tufin, you can automate oversight and provision across your multi-vendor, hybrid network while achieving the continuous compliance necessary to be audit-ready.