Penetration testing, also known as pen testing or ethical hacking, is the practice of testing a computer system, network or web application to find security vulnerabilities that an attacker could exploit. Penetration testing can be performed to comply with security regulations, to test an organization’s security posture, or to improve security measures and fix vulnerabilities before they can be taken advantage of by real attackers.
What is penetration testing?
Penetration testing simulates the actions of a real attacker exploiting weaknesses in security to gain unauthorized access to systems and data. The goal is to identify security vulnerabilities that could be leveraged by malicious actors so they can be fixed before a real breach occurs.
There are several different types of penetration tests:
- Network penetration test – Targets the network infrastructure and seeks to circumvent network security controls.
- Web application penetration test – Assesses a web application for vulnerabilities like SQL injection, cross-site scripting, etc.
- Mobile application penetration test – Checks mobile apps for insecure data storage, lack of binary protections, etc.
- Social engineering – Tests the susceptibility of people to phishing, pretexting and other social engineering attacks.
- Physical penetration test – Attempts to gain physical access to facilities to evaluate physical security controls.
- Client-side penetration test – Targets software vulnerabilities in desktop apps, workstations and laptops within the organization.
Penetration testers may use various tools and techniques to find and exploit vulnerabilities, including:
- Scanning for vulnerabilities with automated tools like Nessus.
- Attempting to circumvent firewalls and intrusion detection systems.
- Cracking password hashes.
- Finding and utilizing unpatched software vulnerabilities.
- Executing denial-of-service attacks.
- Phishing and social engineering.
The penetration tester will document all findings and work with the organization to remediate any vulnerabilities before they can be exploited by real attackers. Companies can then utilize the penetration test results to improve their overall security posture.
Why is penetration testing important?
There are several key reasons why regular penetration testing is important for any organization:
- Find security holes before hackers do – Penetration testing helps identify vulnerabilities that real-world attackers could use to breach systems and access sensitive data. Finding them first allows companies to fix the problems.
- Fulfill compliance requirements – Some industries like finance and healthcare have regulations that require frequent penetration testing and vulnerability assessments.
- Validate security controls – Penetration testing can validate that security measures like firewalls, IDS and encryption are functioning effectively.
- Increase security awareness – Showing employees how their systems can be compromised improves awareness and highlights the importance of security.
- Prioritize remediation efforts – Knowing which vulnerabilities pose the biggest risks helps IT teams focus on fixing the most critical issues first.
Without regular penetration testing, organizations leave themselves open to being breached by hackers exploiting vulnerabilities that could have been identified and fixed ahead of time.
What does a penetration test involve?
A full penetration test will include multiple phases, such as:
- Planning – Defining the scope and goals for the pen test, choosing a test team, and scheduling testing windows.
- Reconnaissance – Gathering information on the target systems, networks and applications before hands-on testing begins.
- Scanning – Running vulnerability scanners to identify known security holes.
- Exploitation – Actively exploiting vulnerabilities to achieve deeper penetration into systems and networks.
- Maintaining access – Emulating post-exploitation actions taken by attackers to maintain persistent access.
- Analysis – Assessing findings from testing and turning them into actionable remediation strategies.
- Reporting – Documenting all vulnerabilities found and how they were exploited in a detailed report.
- Remediation – Fixing vulnerabilities based on the pen test report and implementing improvements to security controls.
Professional penetration testers will also conduct tests that minimize disruption to business operations. Testing is done in a controlled manner and planned around change windows and maintenance periods whenever possible.
What is included in a penetration testing report?
The deliverable for a penetration test is typically a detailed report on findings and recommendations for improving security. This written report will generally contain:
- An executive summary of key findings.
- A description of the testing methodology and scope.
- Detailed descriptions of each vulnerability found, how it works and steps to reproduce it.
- The risk level of each vulnerability.
- Proof-of-concept evidence such as screenshots demonstrating exploitation.
- List of all hosts/services/web applications tested.
- Recommendations and specific guidance on how to fix each vulnerability.
- Advice on improving overall security measures.
The report provides a roadmap for the client’s IT and security teams to follow when prioritizing and implementing remediation efforts after the pen test.
What are the different types of penetration testing?
There are several different classifications of penetration testing that focus on different assets within an organization:
Network penetration testing
A network penetration test targets the infrastructure and network devices like routers, switches and firewalls. The goal is to find ways to breach the external perimeter defenses and move laterally within the network.
Web application penetration testing
Web app penetration testing assesses the security of web applications and APIs. Testers will probe for vulnerabilities like SQL injection, cross-site scripting, insecure authentication etc.
Mobile application penetration testing
Mobile app pen testing evaluates the security of mobile apps across iOS, Android and other platforms. The goal is to identify vulnerabilities like insecure data storage, lack of binary protections, etc.
Client-side/remote penetration testing
This test targets software vulnerabilities present within workstations, laptops and desktops in an organization by emulating remote attacks across the internet.
Internal penetration testing
Internal testing assumes a threat actor is already inside the network and focuses on lateral movement and privilege escalation post-breach.
External penetration testing
External pen testing mimics internet-based attacks to identify ways to breach the digital perimeter and gain initial access to internal systems and networks.
Social engineering testing
Social engineering testing evaluates human vulnerability to manipulation techniques like phishing, pretexting or impersonation attacks.
Physical penetration testing
Physical pen testing attempts to physically access facilities, servers or data centers and gain access to assets through on-site weaknesses.
How often should penetration testing be performed?
Most organizations conduct regularly scheduled penetration tests on an annual or semi-annual basis. However, the frequency should be determined by factors like:
- Industry regulatory requirements
- Organization’s risk tolerance
- Threat landscape
- Frequency of changes to IT systems and networks
Organizations in highly regulated industries like finance and healthcare often pen test multiple times per year. Companies with large, complex networks and many web/mobile applications may test more frequently as well.
To determine your ideal penetration testing frequency, consider:
- Have any new major applications, networks or systems been implemented since the last pen test?
- Are you operating in a high cyber risk environment due to emerging threats?
- Are you seeing an increasing number of attempted attacks against your systems?
- Have any recent security incidents or breaches occurred at your company?
- Will more frequent testing help fulfill compliance requirements?
If you answer yes to some of these questions, it may make sense to test more often than the industry average.
Should all types of penetration testing be performed each time?
It often isn’t necessary, practical or cost-effective to perform every type of pen test during every single assessment. The types of testing to conduct should be chosen based on:
- Primary objectives for that round of testing
- Most critical potential vulnerabilities
- Systems that have been changed or added since the last test
- Any recent security incidents
- Testing coverage from the previous assessment
For example, an organization might focus primarily on infrastructure penetration testing one year, and then shift to concentrate more on web application testing the next year once infrastructure remediation is complete.
Social engineering and physical penetration tests do not need to be run every single time, as they can monitor human processes that usually do not change as frequently as technology.
A qualified penetration testing firm can advise on striking the right balance of testing coverage across different assets over time.
What regulations require penetration testing?
Some of the key regulations that mandate regular penetration testing and vulnerability assessments include:
- Payment Card Industry Data Security Standard (PCI DSS) – Requires pen testing networks annually and after any significant changes. Also requires web application security assessments for any customer-facing web apps.
- Health Insurance Portability and Accountability Act (HIPAA) – Requires entities to conduct risk analyses and perform risk management, with penetration testing recommended as a best practice.
- Sarbanes-Oxley Act (SOX) – Does not explicitly require penetration testing but does require internal control assessments which often includes security testing.
- Gramm–Leach–Bliley Act (GLBA) – Requires regular network and system security assessments, with pen testing the most rigorous way to meet assessment requirements.
Additionally, cyber insurance policies may require a minimum frequency of penetration testing to qualify for policy coverage and favorable rates.
What are important considerations when choosing a penetration testing company?
Key criteria to evaluate when selecting a penetration testing service provider include:
- Experience – The company should have extensive expertise across different types of penetration testing and methodologies.
- Certifications – Preference for testers that hold respected certs like Offensive Security Certified Professional (OSCP), Certified Ethical Hacker (CEH) etc.
- Reputation – Positive references from current and former clients.
- Reporting – Ability to deliver clear, insightful reports with actionable remediation advice.
- Compliance – Necessary qualifications to perform tests for compliance with regulations like HIPAA, PCI DSS etc.
- Communication – Responsiveness to questions and regular status updates during testing.
- Price – Competitive and transparent pricing, though price should not be the only determining selection factor.
A vendor with technical expertise, good communication practices and satisfied customers is more likely to provide maximum value from your penetration testing program.
What tools do penetration testers use?
Penetration testers leverage a wide range of tools and technologies during different phases of testing, including:
| Category | Common Tools |
|---|---|
| Scanning and enumeration | Nmap, Netcat, Nessus, OpenVAS |
| Vulnerability exploitation | MetaSploit, Burp Suite, OWASP ZAP |
| Wireless security | Aircrack-ng, Kismet |
| Web application testing | Nikto,Arachni, w3af |
| Network sniffing | Wireshark, tcpdump |
| Password cracking | John the Ripper, Hashcat, Hydra |
| Social engineering | SET, Phishery, Evilginx |
| OSINT gathering | Maltego, FOCA, Recon-ng |
Advanced penetration testing tools like Cobalt Strike and Metasploit enable extensive post-exploitation actions as well.
How can I get started with penetration testing?
Organizations new to penetration testing should follow these steps to get started:
- Define objectives and expected outcomes for your penetration testing program.
- Determine the scope – assets, data and systems that will be tested.
- Develop a budget and secure necessary funding.
- Research and select a qualified penetration testing company that best fits your needs.
- Create a project plan and schedule testing windows.
- Alert staff to testing periods and gather necessary information for the penetration testers.
- Coordinate logistics like network/VPN access for remote testing teams.
- Determine communication protocols for interacting with testers before, during and after testing.
- Review the penetration test report once delivered and start remediating.
- Conduct recurring penetration tests on an annual, biannual or quarterly basis.
New companies may want to start with non-intrusive external testing or a single major system before expanding to broader internal testing across the entire enterprise. An experienced penetration testing firm can provide guidance on the ideal starting point.
What are the benefits of penetration testing services?
The main advantages of partnering with a qualified third-party penetration testing service provider are:
- Expertise – Draws on their extensive experience performing security tests across many industries.
- Objectivity – Unbiased findings since they have no internal technology or processes to protect.
- Efficiency – Allows internal IT teams to focus on daily tasks rather than learning and executing tests.
- Cost – Only pay for services delivered rather than having dedicated in-house testing staff.
- Staffing flexibility – Can scale the size of the testing team up and down based on needs.
- Awareness – Testing personnel often have the latest insight on emerging attack methods and threats.
- Remediation guidance – Provides specific and actionable strategies for improving security based on findings.
The main downside of outsourcing penetration testing services is the loss of institutional knowledge that comes with in-house testing. However, the benefits often outweigh the costs for most organizations with limited security budgets and staff.
Conclusion
Regularly conducting penetration testing provides enormous value for securing sensitive systems and data from constantly evolving cyber threats. While no organization can be 100% secure, proactively finding and fixing vulnerabilities provides strong protection and allows companies to improve their security posture over time.
Using qualified third-party security firms for penetration testing leverages external expertise while minimizing resource strain on internal teams. With careful planning and execution, a high-quality penetration testing program can significantly enhance an organization’s resiliency against attack.