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What Is Firewall Audit? Why Your Organization Need Firewall Audit

Cyber security 10/31/2019 - 16:54 by Swami Nathan

What is a Firewall?

A firewall is a system that prevents unauthorised access to or from a private network. In either hardware or software type, or a combination of both, you can implement a firewall. Firewalls prevent unauthorised internet users from accessing internet-connected private networks, including intranets. All messages that enter or leave the intranet (the local network you are linked to) should go through the firewall, which reviews each message and blocks those that do not meet the security requirements defined.

What are the Types of firewalls?

Packet filtering firewall

Packet filtering firewalls function directly in line at junction points where machines such as switches and routers do their job. Nevertheless, these firewalls do not route packets, but rather compare each packet received with a set of specified criteria — such as the permitted IP addresses, packet size, port number, and other attributes of the packet protocol headers. Packets that are flagged as troublesome are, typically, unceremoniously dropped— that is, they are not transferred and thus wither away.

Circuit-level gateway

Using another relatively quick way to identify malicious code, circuit-level gateways track TCP handshakes and other network protocol login messages across the network as they are formed between physical and virtual hosts to decide whether the login session is legitimate — whether the remote process is deemed to be trusted. We do not, however, examine the packets directly.

Stateful inspection firewall

Stateful inspection firewallState-aware devices, on the other hand, not only examine each packet, but also keep track of whether or not that packet is part of an established TCP or other network session. This offers more security than either packet filtering or circuit monitoring alone but exacts a greater toll on network performance.

Application-level gateway

This type of device— technically a proxy and quite often referred to as a proxy firewall — combines some of the attributes of packet filtering firewalls with that of the circuit-level gateways. We philtre packets not only by the network for which they are intended — as specified by the destination port — but also by certain other attributes, such as the HTTP request list.

While gateways filtering the application layer provides fairly significant data security, they can have a dramatic impact on network performance.

Typical NGFW incorporates packet inspection with state-of–the-art testing and also provides a range of deep packet inspection, as well as other network security mechanisms, such as intrusion detection / prevention, malware filtering and antivirus.

While the packet inspection in standard firewalls just looks at the protocol header of the packet, the deep packet inspection looks at the individual packet data. A deep packet inspection firewall monitors the progress of a web browsing session and is capable of observing whether a packet payload, if combined with other packets in an HTTP server response, constitutes a genuine HTML formatted response.

How firewall work?

A network firewall works by establishing a border between the web and therefore the network it guards. it’s inserted inline across a network affiliation and inspects all packets getting into the network. because it inspects, a rules engine distinguishes between traffic that’s benign and traffic that’s doubtless dangerous.

A firewall isn’t capable of creating judgments on its own — no laptop is. Instead, it follows programmed rules created by humans. These rules dictate whether or not the firewall ought to let a packet through the network barrier. If a packet matches a pattern that indicates danger, the corresponding rule can instruct the firewall to not let the packet through. These rules need to be perpetually updated as a result of the factors for what patterns indicate a dangerous packet amendment oft.

What is Firewall Audit?

Network security audits are becoming a great deal of coverage recently due to standards like SOX, PCI-DSS, and HIPAA. although you do not ought to accommodate any of these standards – nonetheless – business relationships with partners or customers could need you to indicate that your network is secure. However, on the far side compliance necessities, firewall audits are best observe for an awfully sensible reason. They increase your possibilities of catching weaknesses in your network security posture and finding places your policies ought to be tailored. They conjointly facilitate prove you have got been doing all your due diligence in reviewing your security controls and policy controls, must you ever ought to reply to a cause, breach or restrictive issue that decision your security standards into question.

"Your firewall Won't manage itself!"

Firewalls need continuous maintenance to supply best security for your business. Teceze thus recommends regular firewall audits.

Unfortunately, it’s common for a recently put in firewall to be static with regards to rules and security settings. you’ll assume you’re protected however in reality you have got no or restricted protection.

What are the Firewall audit checklist?

Gather Key data before beginning the Audit

Without understanding what’s in your network, you have got no likelihood for fulfillment come back audit time. therefore before undergoing Associate in Nursing audit, certify you’ll collect all relevant security policies and firewall logs (then you’ll analyze the logs against the firewall rule base to grasp what’s truly being used). certify you have got a diagram of this network and firewall topologies. Gather all documentation from previous audits, together with firewall rules, objects and policy revisions. Review relevant firewall marketer data together with OS version, latest patches and default configuration. perceive what servers and data repositories are within the network similarly as their relative worth to the corporate.

Once you’ve gathered this data, it’s imperative that you simply will combination and update this data in one thing higher than a computer program as a result of you are possibly attending to have multiple audits p.a. and computer program compliance sometimes lands up badly.

Review Your Firewall amendment Management method

A good amendment management method is crucial to make sure correct execution and traceability of firewall changes, similarly as property over time to make sure continuous compliance vs. point-in time compliance. Poor documentation of changes, together with why the amendment is required, UN agency licensed the amendment, etc. and poor validation of the impact on the network ar 2 of the foremost common problems once it involves amendment management. certify you have got regular reviews of the procedures for rule-base maintenance which you’ll determine:

  1. If there’s a proper and controlled method in situ to request, review, approve and implement firewall changes.
  2. whether or not or not all of the changes are licensed. If you discover unauthorized rule changes, flag them for any investigation.
  3. If period of time observation of amendments to the firewall is enabled and access to rule change notifications is granted to licensed personnel. Taking these recommendations into consideration can get you off to a decent begin with natural action your firewall amendment management processes and guaranteeing continuous compliance.

Audit the Firewall Physical and OS Security

This is vital to assist shield against the foremost elementary kinds of attack. certify you’ll outline and enforce company baselines… and report against them therefore you recognize wherever you stand. By coverage against these baselines that you simply confirm, you’ll forever be “in the know” of your firewalls’ configuration standing and the way they pull together to the policy. guarantee your firewalls and management servers ar physically secured with controlled access which the OS passes common hardening checklists.

Cleanup and Optimize Your Rule Base

Removing firewall muddle and optimizing the rule base will greatly improve IT productivity and firewall performance. in addition, optimizing firewall rules will considerably cut back a great deal of superfluous overhead within the audit method.

Over time, firewall policies have additional and additional rules more, removed and altered, and ofttimes with very little documentation for the what, why, who, etc. This creates superfluous overhead within the audit method and slows down firewall performance. establish and take away unused rules and objects similarly as lined rules, consolidate similar rules and tighten too permissive rules (i.e. “ANY” within the supply address).

Conduct a Risk Assessment and remedy problems

Essential for any firewall audit, a comprehensive risk assessment can determine risky rules and make sure that rules square measure compliant with internal policies and relevant standards and laws.

When reviewing firewall rules and configurations, you would like to be able to determine any doubtless “risky” rules. what’s “risky” is completely different for every organization reckoning on the network and therefore the level of acceptable risk, however there square measure several frameworks and standards you’ll leverage that give an honest reference, additionally to your own definitions in fact. Risky rules ought to be prioritized by severity. Once you have passed through your list of risk analysis queries, then it’s time to document And assign an action arrange for correction of risks and compliance exceptions found in risk analysis. Once you have conducted correction efforts, check that you document those in addition and verify that these efforts and any rule changes are completed properly.

Current Audits

Now that you just have with success audited your firewall and secured its configuration, you would like to make sure the right steps square measure in situ to make sure continuous compliance.

  1. Guarantee a method is established for continuous auditing of firewalls.
  2. Think about replacement erring manual tasks with machine-driven analysis and news.
  3. Guarantee all audit procedures square measure properly documented, providing a whole audit path of all firewall management activities.
  4. Check that that solid firewall amendment workflow is in situ to sustain compliance over time.
  5. Guarantee there’s alerting system in situ for important events or activities, like changes in sure rules or the invention of a replacement, high severity risk within the policy.

Firewall Log instrument

A firewall may be a key element within the network of your establishment. It provides the ability of network directors to manage traffic flows to and from the network. Analyzing firewall logs keeps you recent on all transactions between the computer network and net of your organisation, or other external network. Here square measure some doable uses to analyse firewall logs:

Teceze instrument as an auditing tool for firewalls

  1. List all connections denied by the firewall and flag the weird connections.
  2. Show your network with all remote and VPN connections.
  3. Performs comprehensive log management and analysis of firewalls.
  4. Presents comprehensive info to assist you track firewall activity in predefined firewall audit reports.
  5. Show reports in table, list, and graph formats with support for multiple sorts of graphs.
  6. Sends predefined or customization warnings in real time via SMS or email.
  7. Identifies suspicious activity and by means of correlation rules alerts the administrator.
  8. Displays in an exceedingly straightforward click the raw log knowledge from documents.
  9. Monitor any changes to the foundations that square measure supported the firewall.
  10. Pick up and stop doable attacks on security.


Why Firewall audit is important?

Once a firewall is in situ, activity regular firewall audits at a minimum on AN annual basis is important to the protection of any business. Annual audits increase the probabilities of catching any weaknesses in your network’s security. additionally to the firewall-related code, security controls and policy controls ought to even be reviewed and tailored PRN to deal with technology or business changes.

Why Teceze for Firewall Audit?

  1. Experienced and Certified Security Consultants
  2. 24/7 Security Incident Response Team
  3. claimable and adjustable, in order that product will increase along with your business desires.
  4. 100 percent Guarantee of client Satisfaction

The only way to protect what you’ve worked hard to build is to be vigilant when it comes to cybersecurity. If you’d like to know more about how your business can benefit from managed services, just give us a call, we are here to help.

Firewall audits require that each new rule is pre-analyzed and simulated prior to being implemented, and that a full audit log of the change is created.