What Is Penetration Testing? A Plain-English Guide for Australian Businesses
If you’ve been told your business needs a penetration test, or you’re trying to tick a compliance box, you might be wondering what actually happens during one. The term gets thrown around a lot, but the explanation is often vague or buried in jargon.
Here’s the short version: penetration testing is a controlled, authorised attempt to break into your systems the same way a real attacker would. The goal is to find security weaknesses before someone with bad intentions does.
Think of it like hiring someone to try every door and window in your building to see which ones are unlocked. Except instead of physical doors, we’re testing your network, applications, cloud environment, and anything else that could be exploited.
Why Businesses Get Penetration Tests
Most businesses come to us for one of three reasons.
First, they’re required to. Regulations like APRA CPS 234 for financial services, or compliance frameworks like ISO 27001 and SOC 2, often require regular penetration testing as evidence that you’re managing risk properly. If you’re a government supplier, the ASD Essential Eight maturity levels also expect some form of security testing depending on your target level.
Second, they’ve had a close call. Maybe a phishing email got through, or they discovered a misconfigured server that was publicly accessible for months. These near-misses tend to focus attention quickly.
Third, they’re being proactive. These are the businesses that understand their reputation, customer data, and revenue depend on security. They’d rather find problems on their own terms than wait for a breach to happen.
What Actually Happens During a Penetration Test
A penetration test is not a scan you run once and forget. It’s a structured, hands-on assessment carried out by experienced security professionals who think like attackers.
Here’s the typical process.
We start with reconnaissance. This means gathering information about your organisation, your systems, your technologies, and your attack surface. Some of this is done passively (looking at publicly available information), and some is done actively (probing your network or applications to see how they respond).
Next comes vulnerability identification. We look for weaknesses: outdated software, misconfigurations, weak authentication, poor access controls, or logic flaws in custom applications. This isn’t just running a vulnerability scanner and handing you a report. Scanners are a starting point, but the real work is manual testing to understand whether a detected issue is actually exploitable.
Then we attempt exploitation. This is where we try to leverage the vulnerabilities we’ve found to gain access, escalate privileges, move laterally across systems, or extract data. The goal is to understand what an attacker could realistically achieve, not just what’s theoretically possible.
Finally, we document everything and provide a report. A good penetration test report explains what we found, how we exploited it, what the business impact is, and how to fix it. The findings are prioritised by risk, so you know what to tackle first.
If you’re not sure where your organisation stands or whether you’re ready for a formal pentest, a security gap analysis is a good starting point. [Siege Cyber offers these as a standalone service].
Types of Penetration Testing
Penetration testing isn’t one-size-fits-all. The type you need depends on what you’re protecting and where your risks sit.
External penetration testing simulates an attack from outside your network. This is what most people think of when they hear “pentest.” We’re testing your internet-facing systems: websites, web applications, VPNs, mail servers, anything exposed to the public.
Internal penetration testing assumes the attacker is already inside your network. This could be a malicious insider, or an external attacker who’s gained initial access through phishing or a compromised laptop. Internal tests focus on what an attacker can do once they’re past the perimeter.
Web application testing focuses specifically on your custom applications or online platforms. This includes testing for issues like SQL injection, cross-site scripting, broken authentication, and insecure APIs. If you’re a SaaS business or you handle customer data through a web portal, this type of testing is critical.
Cloud penetration testing targets your cloud infrastructure, whether that’s AWS, Azure, or Google Cloud. Misconfigurations in cloud environments are one of the most common causes of data breaches, and the shared responsibility model means you can’t assume your provider is handling security for you.
Wireless testing assesses the security of your Wi-Fi networks, looking for weak encryption, rogue access points, or the ability to intercept traffic.
Most businesses start with an external test, then move to internal or application-specific testing once they’ve addressed the basics.
How Often Should You Run a Penetration Test?
This depends on your risk profile and your compliance obligations, but a good rule of thumb is annually at minimum.
If you’re in a regulated industry, annual testing is usually the baseline. ISO 27001, for example, doesn’t mandate a specific frequency, but auditors expect regular testing as part of your ongoing risk management. SOC 2 audits often require evidence of penetration testing within the audit period. APRA CPS 234 requires entities to test security controls regularly, and for many organisations that means at least once a year.
That said, annual testing is the floor, not the ceiling. If you’re making significant changes to your environment (launching a new application, moving to the cloud, opening a new office network), you should retest those areas. Threat landscapes change, vulnerabilities are discovered, and configurations drift. A test from 12 months ago might not reflect your current risk.
Some of our clients run continuous or quarterly testing, especially for web applications or external infrastructure. This is more common in tech companies, financial services, or anywhere the attack surface is constantly changing.
What to Expect From a Penetration Test Report
A penetration test is only as good as the report that comes out of it.
You should expect to see a clear executive summary that explains what was tested, what was found, and what the business impact is. This section is for decision-makers who don’t need to understand the technical details but do need to understand the risk.
The technical findings should include detailed descriptions of each vulnerability, proof of exploitation, screenshots or evidence, and clear remediation advice. Findings should be rated by severity (critical, high, medium, low) so you know where to focus your effort.
A good report also includes a retest offer. Once you’ve implemented fixes, the testers should verify that the issues have been properly resolved. Some providers charge extra for this. At Siege Cyber, a retest is included as standard.
Who Should Be Doing Your Penetration Test?
Not all penetration tests are created equal.
You want testers who have real-world experience, not just certifications. Look for people who’ve spent time in offensive security roles, who understand both the technical side and the business context, and who can explain findings in a way that helps you make decisions.
You also want independence. A penetration test carried out by the same people who built or manage your infrastructure is not going to give you an objective view.
In Australia, if you’re in a regulated industry, your auditor or regulator may have specific requirements about who can conduct testing and what credentials they need to hold. It’s worth checking this before you engage someone.
Final Thoughts
Penetration testing isn’t just a compliance checkbox. It’s one of the most effective ways to understand your real security posture and find problems before they turn into breaches.
If you’re an Australian business dealing with customer data, financial information, or regulated systems, penetration testing should be part of your security programme. The cost of a test is a fraction of the cost of a breach, both financially and reputationally.
Siege Cyber has been helping businesses across Australia with penetration testing, compliance, and cyber risk for over 20 years. If you’d like to discuss what type of testing makes sense for your organisation, or if you’re preparing for an ISO 27001 or SOC 2 audit and need testing as part of that process, get in touch.
You can reach us at siegecyber.com.au or email [email protected] directly. We’re based in Brisbane but work with clients across the country.