Pentest: Types of penetration tests, methods and implementation

The average cost of a data breach in France in 2025 is €3.59 million per incident, approximately 71 TFPs less than in 2024 (≈ €3.85 million). This demonstrates the importance of penetration testing to assess the IT security of businesses. For French SMEs, a successful cyberattack represents an average of €466,000, with an impact that can reach up to 101 TFPs of revenue, according to analyses based on the work of the...’ANSSI and the Court of Auditors.

A penetration test replicates the techniques of a real attacker in a controlled and legal environment. It allows companies to discover their vulnerabilities, measure their security level, and prioritize their remediation efforts.

In this article, you will discover the different types of pentest, the black box, grey box and white box methods, as well as the key steps to successfully carry out a penetration testing project in a company.

Key points to remember

Penetration testing is a crucial pillar of any modern cybersecurity strategy. Here are the key points to keep in mind before you begin:

A pentest is the controlled application of attacker techniques on a defined perimeter.
The objective is to identify and exploit the technical vulnerabilities of your information system, within a structured framework, in order to correct them before a hacker can take advantage of them.

The main types of pentest cover your entire attack surface: application (web, mobile, API), infrastructure and network, Red Team and social engineering. Each type serves specific purposes depending on your context.

The Black Box, Grey Box and White Box approaches determine the level of information provided to the pentester before the test. The choice depends on the desired level of realism and the desired depth of analysis.

Penetration testing can be part of a compliance framework (ISO 27001, PCI DSS, SOC 2) and complements other security measures. such as vulnerability scans, audits, and bug bounty programs.

The value of a penetration test depends both on the quality of the approach (methodology, expertise, tools) and on how the results are presented (clear report, prioritized recommendations, exchange with the teams).

What is a penetration test in cybersecurity?

The term pentesting comes from the English “penetration test,” translated into French as test d'intrusion. It refers to a security assessment during which an expert replicates the techniques used by hackers to compromise a computer system, a web application, or a network.

The goal of a penetration test is to discover vulnerabilities before a malicious attacker does. Penetration testers analyze the potential impact of vulnerabilities according to the CIA triad: data confidentiality, information integrity, and service availability. This approach allows them to measure the actual risk to the company.

The test is conducted within a strict contractual framework. A letter of engagement defines the dates, scope, authorized systems, and rules of engagement. Without this written authorization, the same actions would constitute a cybercrime.

Let's take a concrete example: a French e-commerce company commissions a penetration test of its website and mobile application in September 2025, three months before the end-of-year sales peak. The goal is to identify and fix security issues before cybercriminals attempt to steal customer payment data.

Pentesting: Ethical and Regulated Hacking

A malicious hacker exploits vulnerabilities to steal, destroy, or extort. A penetration tester uses the exact same techniques, but with the opposite goal: to strengthen the security of a system.

A penetration tester is a certified professional who typically holds recognized qualifications such as OSCP, eJPT, or CEH. Their role is to identify vulnerabilities, exploit them in a controlled manner, and demonstrate their impact to the client. Unlike hackers, they always operate with the explicit consent of the system owner.

All actions performed during a penetration test are logged: network scans, exploitation attempts, privilege escalation, simulated data exfiltration. These logs feed into the final report and ensure the mission's transparency.

Imagine a login form vulnerable to SQL injection. The penetration tester exploits this vulnerability to access the customer database, then meticulously documents the method used and the data accessed. They do not actually modify or exfiltrate this sensitive information.

Ethics govern each step: written agreement from the owner, adherence to the defined scope, confidentiality of results, and compliance with regulations, particularly the GDPR in Europe. A penetration tester who exceeds these limits risks legal action.

Objectives and benefits of a penetration test

A well-conducted penetration test generates concrete and measurable benefits for the company:

Reducing the risk of cyberattacks is the primary benefit. By identifying exploitable vulnerabilities, you prevent ransomware attacks, data theft, and sabotage before they occur. A vulnerability discovered by a penetration tester costs infinitely less than a breach exploited by an attacker.

The penetration test provides a prioritized view of risks. Each vulnerability is classified according to its criticality (critical, high, medium, low), allowing technical teams to focus their efforts on the most urgent fixes.

Compliance requirements often trigger penetration testing. Standards such as ISO 27001, SOC 2, PCI DSS, and HDS (Health Data Hosting) mandate regular security assessments. In the healthcare, finance, and B2B SaaS sectors, large enterprise clients frequently require penetration test reports before signing a contract.

The educational effect is an often underestimated benefit. The concrete results of the test raise awareness among developers, administrators, and business users about best security practices. Seeing a vulnerability exploited in one's own code makes a stronger impression than theoretical training.

The main types of penetration testing

The attack surface of a modern enterprise extends far beyond the website itself. It encompasses mobile applications, APIs, cloud infrastructures, connected objects (IoT), internal networks, and even the human factor.

Several types of tests can be combined in a single mission. For example, a web penetration test combined with an internal network test and a phishing campaign provides a comprehensive view of threat exposure.

The choice of penetration testing types depends on the context: deployment of a new service, recent security incident, customer requirement, or preparation for certification. Mature companies typically plan a comprehensive annual penetration test, supplemented by targeted tests before each major application deployment.

web application penetration testing

Web application penetration testing targets websites, customer portals, back-office systems, and business applications exposed to the internet. It is the most frequently requested type of testing, as web applications often constitute the primary entry point to the information system.

The vulnerabilities sought generally follow the OWASP Top 10 repository:

• SQL injections allowing access to the database
• Cross-Site Scripting (XSS) to steal user sessions
• Cross-Site Request Forgery (CSRF) to execute actions without the user's knowledge
• Server-Side Request Forgery (SSRF) to access internal resources
• Incorrect authentication and session management configurations

Penetration testers combine manual analysis with specialized tools such as Burp Suite, OWASP ZAP, and Sqlmap. Human expertise remains essential for detecting business logic flaws that automated scanners cannot identify.

In 2024, a major French bank commissioned a penetration test of its online banking portal. The testers identified a vulnerability in the transfer process that allowed the amount to be changed after validation. This discovery prevented potentially significant financial losses.

Mobile application penetration testing

The mobile application pentest covers iOS and Android applications, their associated backend (REST or GraphQL API), local storage on the device, and network communications.

This assessment combines two complementary approaches:

• Static analysis examines the application code (reverse engineering of APK files for Android or IPA files for iOS) to identify hard-coded secrets, dangerous configurations, and vulnerable libraries.
• Dynamic analysis tests the application running on a real device or emulator to observe its behavior, intercept network traffic, and manipulate data.

Typical vulnerabilities include unencrypted storage of sensitive information on the device, TLS certificate validation flaws allowing man-in-the-middle attacks, and bypassing jailbreak or root detection mechanisms.

Frameworks such as Frida, MobSF, or Objection are used to instrument the application and bypass its protections.

A French fintech company preparing to launch its mobile payment app in 2026 commissioned a comprehensive audit. Penetration testers discovered that authentication tokens were stored in plain text within Android shared preferences, allowing any malicious application to retrieve them.

API and microservices penetration testing

Web APIs (REST, GraphQL, gRPC) now form the connective tissue of modern applications. They expose functionalities to partners, mobile applications, and web frontends, making them prime targets for attackers.

Specific API risks are catalogued in the OWASP API Security Top 10:

• BOLA (Broken Object Level Authorization): access to other users' data by modifying an identifier
• Incorrect management of permissions between roles
• Insufficient rate limiting allowing brute-force or scraping
• Excessive data exposure in the responses
• Injection into query parameters

A common example illustrates these risks: a B2B SaaS API allowed a user to view other customers' invoices simply by modifying the numerical identifier in the URL. This IDOR (Insecure Direct Object Reference) vulnerability could have exposed the confidential data of hundreds of client companies.

Any migration to microservices or cloud-native architectures should include API penetration testing in its planning. The increased number of entry points mechanically increases the attack surface.

Infrastructure and network penetration testing (internal/external)

Infrastructure penetration testing examines the technical components that support applications: servers, firewalls, routers, VPNs, workstations, Active Directory, and cloud services (IaaS, PaaS).

The distinction between external and internal pentesting is fundamental:

Kind	Point of view	Main targets
External	Attacker via the Internet	Exposed services, public IP addresses, VPN
Internal	Attacker already in the network	Active Directory, internal servers, segmentation

Frequently discovered vulnerabilities include:

• Outdated services with known, unpatched CVEs
• Unnecessary open ports (RDP, SMB exposed to the Internet)
• Default passwords on network equipment
• Insufficient network segmentation allowing lateral movements
• Permissive Active Directory configurations

Typical tools for this type of pentest include Nmap for discovery, Nessus or OpenVAS for vulnerability scanning, Metasploit for exploitation, and BloodHound for Active Directory attack path analysis.

A typical scenario simulates an attacker who has compromised a standard user workstation. The penetration tester demonstrates how, from this entry point, they can escalate their privileges to become a domain administrator and gain access to the production servers.

Purple Team: the synergy between attack and defense

Between the offensive approaches of the Red Teaming and the defensive approaches of the Blue Teaming, the Purple Teaming embodies a collaborative approach where the two worlds work together to continuously improve the security posture. Rather than a simulated confrontation, it is a coordinated exercise: the attackers (Red Team) execute realistic scenarios while the defenders (Blue Team) observe, detect and refine their defense mechanisms.

This approach fosters a direct learning loop, enabling real-time adjustments to detection tools. In practice, a Purple Teaming session transforms each simulated attack into a concrete opportunity for defensive reinforcement. This model is particularly well-suited to organizations already equipped with a mature SOC that wish to measure and improve the operational effectiveness of their detection capabilities.

Red Team and advanced scenarios

THE Red Teaming represents the most advanced and realistic approach to security testing. Unlike a classic penetration test, a Red Team exercise spans several weeks or even months and simulates a complete attack campaign.

The main objective is not to list all the vulnerabilities, but to test the detection and response capabilities of the defense teams: SOC, CERT, CISO. The Red Team operates in stealth mode, seeking to achieve specific objectives, defined beforehand by the client, without being detected.

The scenarios combine several attack vectors:

• Targeted phishing (spear phishing) to gain initial access
• Exploiting a web vulnerability as an alternative entry point
• Lateral movement within the internal network
• Elevation of privileges to administrator accounts
• Simulated exfiltration of sensitive data

This approach is recommended for organizations that are already security mature, have an operational SOC, documented incident procedures, and a mapping of critical assets.

Social Engineering Pentest

Social engineering penetration testing targets what is often considered the weakest link in the security chain: the human factor. Employees, contractors, support teams, and managers are all part of the scope.

Simulated attacks take several forms:

• Campaign awareness
• Sending charges and a booby-trapped link to measure protection mechanisms (SEG, EDR, other security mechanisms)
• Phishing with an accomplice The incident detection and response component of the blue team
• Complete spear phishing scenario, produced in red team
• Physical intrusion : implementation of unauthorized access scenarios to premises (tailgating, social engineering, badge cloning, etc.), with or without the objective of connecting an implant to the internal network or depositing booby-trapped media (USB keys, for example).

The goal is to concretely measure human vulnerability: what percentage of employees click on a suspicious link? How many divulge their password over the phone? Does anyone open the door to a stranger under the pretext of a delivery?

Clear planning beforehand is crucial to avoid demotivating teams. The target population, the scope of the exercise, and post-campaign communication must be precisely defined. The goal is not to trick employees, but to improve overall security.

These tests should be combined with awareness sessions and practical training. A high click-through rate on a phishing campaign becomes a learning opportunity, not a punishment.

Other types of penetration testing (IoT, cloud, industrial systems)

Three specialized areas deserve particular attention:

IoT penetration testing (connected objects) Cameras, sensors, payment terminals, and other connected devices often have critical vulnerabilities. The analysis focuses on firmware (extraction and reverse engineering), radio communications (BLE, Zigbee, LoRa), and associated mobile or web applications. Updates are often unavailable or difficult to deploy.

Pentest cloud Azure, AWS, and GCP environments introduce specific risks related to misconfigurations. Public S3 buckets, overly permissive IAM roles, exposed RDP ports, and secrets stored in clear text within environment variables are common findings. Managed services (databases, serverless functions) also require special attention.

Industrial Pentest (OT/ICS/SCADA) Programmable logic controllers (PLCs), supervisory control and data acquisition (SCADA) systems, and production networks often have long-standing and unpatched vulnerabilities. The main constraint is to avoid disrupting industrial operations. These tests require thorough preparation and are generally conducted during scheduled maintenance shutdowns.

These three areas require highly specialized skills and dedicated tools. Few service providers master all of these environments.

Pentest methods: black box, grey box and white box

The three approaches—Black Box, Grey Box, and White Box—describe the level of information provided to the penetration tester before the project begins. This choice directly influences the realism of the test, its depth of analysis, and its efficiency relative to the available time.

The choice depends on the objectives: simulating a realistic external attack, conducting an in-depth security analysis of a critical application, or optimizing a limited budget. Time constraints and available resources also influence the decision.

In practice, many projects adopt a hybrid approach. For example, a black-box reconnaissance phase followed by targeted gray-box scenarios allows for a combination of realism and efficiency.

These approaches are part of recognized methodologies such as the Penetration Testing Execution Standard (PTES) and OWASP guidelines which structure the conduct of tests.

The same application can be tested successively using different approaches at key moments in its life cycle: black box before production, white box after a major refactoring.

Black box penetration testing

In a black box approach, the pentester only has publicly accessible information: domain name, IP addresses discovered by his own means, interfaces accessible without authentication.

This method closely mimics an external attacker who knows nothing about their target. Its realism is its main strength: the results demonstrate what a motivated hacker could achieve under the same constraints.

The typical steps of a black box pentesting follow a logical progression:

1. OSINT (Open Source Intelligence) collection: research on search engines, social networks, leak databases
2. Asset discovery: network scan, subdomain enumeration, technology identification
3. Identification of vulnerabilities in exposed services
4. Exploiting discovered vulnerabilities

The limitations of this approach are well-known: the analysis is slower because the tester spends time on discovery. Deep flaws, business logic problems, and internal vulnerabilities risk going unnoticed due to a lack of context.

A common example: an international group requires a black box penetration test of its prospective supplier's customer portal before signing a major contract. The test simulates exactly what a malicious competitor might attempt.

Pentest in a grey box (Grey Box)

The grey box approach provides the penetration tester with standard user access or partial documentation. This setup mimics a collaborator, a legitimate customer, or an attacker who obtained credentials through phishing.

This method excels at testing:

• The separation of rights between different roles
• Opportunities for privilege escalation
• Business logic vulnerabilities accessible to authenticated users
• Data protection between tenants in a multi-client application

Time is used more effectively than in a purely black box approach. Discovery phases are accelerated, allowing more effort to be devoted to in-depth analysis of critical functionalities.

Let's take the example of a B2B SaaS platform with three roles: user, manager, and administrator. The penetration tester receives an account of each type and verifies that a standard user cannot access administrative functions, that a manager cannot see other teams' data, etc.

The grey box approach is often recommended for a first comprehensive application penetration test. It offers a good balance between realism and exhaustiveness.

White box penetration testing

White box penetration testing gives the tester maximum access: source code, architecture diagrams, infrastructure configurations, technical documentation and privileged test accounts.

The goal is to search for deep vulnerabilities that are impossible to detect from the outside:

• Business logic errors in the code
• Poor development practices (hard-coded secrets, weak cryptographic algorithms)
• Vulnerabilities in components not directly exposed
• Architectural problems that promote lateral movement

This approach naturally combines with secure code reviews and security unit testing. It integrates well into a DevSecOps framework.

A concrete example: a fintech company is preparing for its PCI DSS certification in 2025. It commissions a full white-box audit of its payment API. The penetration testers gain access to the source code, anonymized production logs, and the complete architecture. They identify a race condition in transaction processing that could have allowed double charges.

White box penetration testing requires close collaboration between penetration testers, developers, and architects. The results are often more comprehensive, but the test demands more preparation and coordination.

Key steps in a penetration test

A structured pentesting follows sequential phases inspired by recognized methodologies such as PTES (Penetration Testing Execution Standard) and NIST SP 800-115. This organization ensures the traceability of actions and the repeatability of tests.

The duration of a penetration test varies considerably depending on the scope. Expect approximately 5 working days for a medium-sized web application, 2 to 3 weeks for a complete infrastructure audit, and up to 4 weeks or more for a Red Team exercise.

Continuous communication between penetration testers and the client is essential. Regular progress updates, secure channels for sensitive exchanges, and an escalation procedure for critical discoveries must be established from the outset.

The penetration testing cycle must be repeated after each major system upgrade and at least once a year to maintain a level of security appropriate to current threats.

1. Defining the scope and framing

This preliminary phase precedes any technical action. It concludes with a framework document validated by both parties, which constitutes the moral and technical contract of the mission.

Typical elements of the scope include:

Element	Examples
Technical targets	URLs, IP addresses, network ranges, application names
Environments	Production, pre-production, development
Test accounts	Provided identifiers, associated roles
Time windows	Beaches where access is permitted, days where it is prohibited
Contacts	Technical contacts, escalation procedure

The rules of engagement define the prohibited actions (no denial of service, no actual exfiltration of customer data), the load thresholds to be respected and the procedures in case of an incident.

For example, an e-commerce site might choose to limit penetration testing to the pre-production environment to avoid any impact on end customers. The test data is anonymized but representative.

The CISO and technical teams must be involved from this stage. Their knowledge of the system and operational constraints is essential to defining a realistic and useful scope.

2. Recognition and information gathering

The reconnaissance phase consists of gathering all available information on the target to map its attack surface.

Public information gathering (OSINT) leverages numerous sources:

• DNS records and WHOIS data
• Search engines (Google, Bing)
• Professional social networks (LinkedIn for identifying employees and technologies)
• Leak databases (Have I Been Pwned, DeHashed)
• Web archives (Wayback Machine)

Technical tools complement this passive search. Nmap scans ports and services, Shodan lists equipment exposed on the Internet, theHarvester collects emails and subdomains, and Amass maps the DNS infrastructure.

This step allows us to draw up an initial map of the attack surface. It sometimes reveals surprises: a forgotten but still accessible administration subdomain, a development server exposed by mistake, or an old version of the application still online.

Even with a limited scope, no action should target unauthorized systems. The line between legitimate reconnaissance and illegal intrusion must remain perfectly clear.

3. Vulnerability Analysis

Vulnerability analysis systematically searches for potential weaknesses based on collected information. It combines automated approaches and manual testing.

Vulnerability scanners like Nessus, OpenVAS, and Qualys identify known flaws: outdated software versions, unpatched CVEs, and dangerous default configurations. For web applications, Nikto and the scanners integrated into Burp Suite complete the toolkit.

Human expertise remains essential for:

• Filter out false positives generated by automated tools
• Contextualize the results according to the environment
• Identifying business logic flaws invisible to scanners
• Discover the chains of minor vulnerabilities

Typical discoveries include an Apache web server in a vulnerable version, a JavaScript library with a critical CVE, a form without server-side validation allowing injections, or an administration service accessible without strong authentication.

Vulnerabilities deemed promising are selected for the next phase. Exploitation will validate their actual impact.

4. Exploitation and post-exploitation

Exploitation transforms a theoretical vulnerability into real access. This is the phase that concretely demonstrates the impact of a flaw on the company.

Exploitation techniques vary depending on the context:

• SQL injection to extract data from the database
• Remote code execution via an unpatched CVE
• Bypassing authentication to access privileged functions
• Exploitation of weak or reused passwords

Post-exploitation measures how far an attacker can go after an initial access:

• Elevation of privileges : switching from a user account to an administrator account
• Lateral movement : reaching other systems from the initial entry point
• Persistence : maintain access despite restarts or password changes
• Access to sensitive data : demonstrate the ability to exfiltrate critical information

Tools like Metasploit, Empire, and CrackMapExec facilitate these operations. For Active Directory environments, BloodHound maps attack paths to privileged accounts.

A classic scenario: the pentester exploits a weak password on a service account, uses it to log into a server, discovers administrative credentials stored in plain text, and demonstrates that he can take complete control of the Active Directory domain.

The truly sensitive data is never used beyond the minimum necessary demonstration. The penetration tester documents what they could have done but did not actually do.

5. Pentest report and feedback

The report is the main deliverable of the penetration test. Its quality determines the true value of the mission for the client.

The typical structure of a report includes:

• Executive Summary : a summary in non-technical language for management, including overall risk level and priority recommendations
• Scope and methodology : reminder of the scope, test conditions and approach used
• Detailed results Each vulnerability is documented with a description, evidence (screenshots, logs, payloads), criticality assessment, and remediation recommendations.
• Attack scenarios : demonstration of fault chains and their business impact
• Technical annexes Raw data, tested configurations, tools used

Each vulnerability is classified by criticality according to an internal grid or the CVSS v3.1 score. The remediation recommendations are concrete and actionable, not vague advice such as “improve security”.

The feedback session typically takes place in a meeting, either in person or via videoconference, with the technical teams and business decision-makers. This session allows for contextualizing the results, answering questions, and prioritizing remediation actions.

A valuable additional deliverable: a one-page managerial summary intended for senior management or investors, simplifying the issues without going into technical details.

Planning a targeted retest allows you to verify the correct implementation of the most critical fixes a few weeks or even months after the initial report.

Pentesting, vulnerability scanning and bug bounty programs: how to choose?

Three complementary approaches can be used to assess the security of a system. Their combination offers optimal coverage.

THE vulnerability scan This is an automated, fast, and inexpensive analysis. It identifies known vulnerabilities (CVEs, default configurations) across a wide range of areas. Its limitations include a high false positive rate, no exploit validation, and an inability to detect business logic flaws. It is an excellent first-line tool for initial diagnosis or ongoing monitoring.

THE pentesting It goes much further. A human expert validates vulnerabilities, exploits them in a controlled manner, and demonstrates their real impact. The analysis is contextualized, false positives are eliminated, and complex flaws are identified. The cost is higher, but the added value is considerable for critical systems.

THE bug bounty This opens up vulnerability research to an external community of researchers via specialized platforms (YesWeHack, HackerOne, Bugcrowd). The compensation model for discovered vulnerabilities is attractive, but requires prior security maturity to sort and correct the flow of reports.

Approach	Forces	Boundaries	Maturity required
Vulnerability scan	Fast, wide, automated	False positives, no exploitation	Weak
Pentest	Deep, contextualized, actionable	One-off payment, higher cost	Average
Bug bounty	Continuity, diversity of approaches	Volume of reports to manage	High

An effective combination for an average company: automated weekly vulnerability scanning, full annual pentest on critical assets, and possibly private bug bounty on the most exposed features.

For an initial diagnosis, start with a scan. For critical systems (payment, personal data, partner access), penetration testing is essential. Bug bounty programs are suitable for organizations with established remediation processes and a mature infrastructure.

Tools and resources commonly used in penetration testing

The pentester's arsenal combines open source and commercial tools, organized by phase of testing.

Reconnaissance and OSINT Nmap remains the reference tool for network discovery and service enumeration. Amass and Sublist3r map subdomains. TheHarvester collects emails and public information. Maltego visualizes relationships between entities. Recon-ng automates reconnaissance workflows. Shodan and Censys catalog devices exposed on the internet.

Vulnerability analysis Nessus (commercial) and OpenVAS (open source) dominate the infrastructure scanning market. Qualys offers a cloud solution for large organizations. For the web, Nikto detects dangerous configurations and exposed sensitive files.

Exploitation Metasploit Framework is the standard for developing and executing exploits. CrackMapExec facilitates attacks on Windows and Active Directory networks. BloodHound graphically maps attack paths to privileged accounts in AD. Impacket provides a collection of Python scripts for manipulating network protocols.

Web and application testing Burp Suite Professional is the central tool for web penetration testers, combining an interception proxy, automated scanner, and extensions via the BApp Store. OWASP ZAP offers a complete open-source alternative. Sqlmap automates the detection and exploitation of SQL injections. Nuclei allows for the execution of vulnerability detection templates at scale.

Work environment Kali Linux remains the leading distribution with over 600 pre-installed tools. Parrot Security OS offers a lighter alternative. Exegol provides a Docker containerized environment with up-to-date tools and an optimized configuration for professional penetration testing.

Frequently Asked Questions (FAQ)

How often should a company conduct a penetration test?

A minimum annual testing frequency is recommended for critical systems handling sensitive data or payments. Beyond this baseline, additional testing should be scheduled before each major production release: launching a new application, significant code refactoring, or cloud migration. High-risk organizations such as banks, telecom operators, or providers of sensitive SaaS software often schedule quarterly or semi-annual testing campaigns. Regulatory requirements like PCI DSS also mandate specific testing frequencies.

Does the penetration test interrupt production services?

The goal is to minimize any impact on operations. The most intrusive tests are scheduled during off-peak hours or on pre-production environments. Certain actions, such as denial-of-service tests or load tests, are generally excluded from the scope unless explicitly requested. If a risk is identified during testing (unstable service, unexpected behavior), penetration testers immediately coordinate with internal teams to suspend the affected action. Proper prior planning and continuous communication reduce these risks to a very low level.

How long does a typical penetration test last?

The duration varies considerably depending on the scope and approach. A targeted web application penetration test typically lasts 3 to 10 business days, depending on the functional complexity. A medium-sized network infrastructure audit takes 1 to 2 weeks, or even months. A full Red Team exercise can last several months for large organizations. The time required depends on the defined scope, the chosen approach (black box takes longer than white box for the same scope), and the desired level of depth.

What is the difference between an internal pentesting test and an external pentesting test?

An external penetration test simulates an attacker coming from the internet, without prior access to the company network. It targets publicly exposed systems: websites, APIs, VPNs, and email servers. An internal penetration test assumes that the attacker already has a foothold in the network, for example, through a compromised workstation, a hijacked VPN connection, or a malicious employee. It assesses network segmentation, Active Directory security, and the protection of internal resources. The two approaches are complementary and often combined in a comprehensive audit.

What to do after receiving a penetration test report?

The first step is to hold a debriefing meeting with the technical teams to fully understand each vulnerability and its context. Next, prioritize fixes based on the indicated criticality: critical and high-risk vulnerabilities should be addressed first. Establish a realistic remediation schedule by involving the relevant teams (development, infrastructure, business). If possible, request a targeted retest to validate that the fixes for the most critical vulnerabilities are effective. Finally, leverage the lessons learned to improve your secure development processes and team awareness.