Qu'est-ce qu'un test d'intrusion (pentest) ?

A penetration test is a simulated cyberattack carried out by cybersecurity experts to identify security vulnerabilities in an information system. Unlike an automated vulnerability scan, a pentest involves a manual offensive approach that replicates the actual techniques used by cybercriminals.

Combien coûte un test d'intrusion pour une PME ?

A penetration test costs between €3,000 and €15,000 depending on the scope and method. An external pentest (black box) on a limited scope starts at around €3,000. A full audit (external + internal + social engineering) can cost between €20,000 and €25,000. The average daily rate for a pentester is between €800 and €1,800.

Quelle est la différence entre un pentest boîte noire, grise et blanche ?

Black box: the pentester has no information and simulates an external attacker. Gray box: the pentester has a standard user account and simulates a malicious employee or post-phishing access. White box: the pentester has access to the source code and architecture. Gray box testing is the most popular because it corresponds to the most common attack scenario.

À quelle fréquence faut-il réaliser un test d'intrusion ?

At least once a year, and after each major IT system upgrade (new application, migration, infrastructure change). Under NIS2, regular penetration testing is recommended to demonstrate compliance. The pentest report is a deliverable that can be used directly by cyber insurers and regulators.

Un test d'intrusion peut-il perturber mon activité ?

A professional pentest minimizes risks thanks to a rigorous methodology and non-destructive tools. An audit agreement clearly defines the rules of engagement, excluded systems, and intervention schedules. It is recommended to schedule tests during low-activity periods and to notify the IT team.

Penetration testing (pentest): why it's vital for your SME [2026]

Penetration testing (pentest): what is it all about?

A penetration test (or pentest) is a simulated cyberattack carried out by cybersecurity experts to identify security vulnerabilities in an information system before a real attacker exploits them. Unlike a simple (automated) vulnerability scan, a pentest involves a manual offensive approach that replicates the techniques used by cybercriminals.

The Verizon DBIR 2025, based on the analysis of more than 22,000 security incidents in 139 countries, shows that the three main vectors of initial access are compromised credentials (22%), exploitation of vulnerabilities (20%, up 34%), and phishing (16%). A penetration test assesses the resilience of your IT system to each of these vectors.

Source: Verizon, Data Breach Investigations Report 2025

Our pentest and audit services →

The 3 types of penetration testing

Black box test

The pentester has no prior information about the target IT system. They work like an external attacker discovering the company for the first time. This type of test evaluates the resistance of the external perimeter (website, VPN, services exposed on the Internet). It is the most realistic test but also the longest, as it includes a reconnaissance phase.

Grey box testing

The pentester has partial information: a standard user account, access to the internal network, or technical documentation. This test simulates a malicious employee or attacker who has already compromised an initial account (post-phishing scenario). This is the most requested type of pentest because it reflects the most common attack scenario.

White box testing

The pentester has access to the source code, network architecture, and administrator accounts. This test is the most comprehensive and allows for in-depth identification of vulnerabilities, particularly in custom-developed applications. It is particularly relevant for code audits and critical applications.

Why a pentest is vital for your SME

SMEs account for more than 50% of cyberattack victims in France (ANSSI). However, the Verizon DBIR 2025 reveals that ransomware is present in 88% of breaches targeting SMEs. The average cost of a data breach is $4.44 million worldwide (IBM 2025), and SMEs take an average of 3 to 5 days to shut down completely after a successful attack. A pentest identifies vulnerabilities before they are exploited and produces a prioritized remediation plan.

Sources: Verizon DBIR 2025 — IBM Cost of a Data Breach 2025

The process of a penetration test

A professional pentest follows a structured methodology, generally based on PTES (Penetration Testing Execution Standard) or OWASP (for web applications) standards. Phase 1: scoping and defining the perimeter (1-2 days). Phase 2: reconnaissance and information gathering. Phase 3: identifying vulnerabilities. Phase 4: exploitation of identified vulnerabilities. Phase 5: privilege escalation and lateral movement. Phase 6: report writing with evidence, criticalities, and remediation plan. The pentest report is a deliverable that can be directly used for NIS2 compliance and cyber insurance requirements.

Pentesting and hardening: two complementary approaches

Pentesting identifies vulnerabilities, while hardening fixes them. In our experience, pentesting recommendations always include hardening workstations and servers (disabling SMBv1, restricting PowerShell, LAPS, etc.) and securing Active Directory. The two services follow on naturally from one another: pentesting → hardening → retesting to validate the fixes.

Discover our solutions: hardening of workstations →

‍

FAQ - Penetration testing (pentest) | Frequently asked questions about cybersecurity

FAQ — Penetration testing (pentest)

Answers to frequently asked questions about our penetration testing services.

A penetration test is a simulated cyberattack carried out by cybersecurity experts to identify security vulnerabilities in an information system. Unlike an automated vulnerability scan, a pentest involves a manual offensive approach that replicates the actual techniques used by cybercriminals.
A penetration test costs between €3,000 and €15,000 depending on the scope and method. An external pentest (black box) on a limited scope starts at around $3,000. A full audit (external + internal + social engineering) can cost between $20,000 and $25,000. The average daily rate for a pentester is between $800 and $1,800.
Black box: the pentester has no information and simulates an external attacker. Gray box: the pentester has a standard user account and simulates a malicious employee or post-phishing access. White box: the pentester has access to the source code and architecture. The gray box is the most popular because it corresponds to the most common attack scenario.
At least once a year, and after each major IT system upgrade (new application, migration, infrastructure change). Under NIS2, regular penetration testing is recommended to demonstrate compliance. The pentest report is a deliverable that can be used directly by cyber insurers and regulators.
A professional pentest minimizes risks thanks to a rigorous methodology and non-destructive tools. An audit agreement clearly defines the rules of engagement, excluded systems, and intervention schedules. It is recommended to schedule tests during low-activity periods and to notify the IT team.

‍