A black box security audit, also known as a black box penetration test, is a method of evaluating the security of an IT infrastructure or system where the testers have no prior knowledge of the target. In other words, they act as if they are examining a “black box” without having detailed internal information about how it works.

Here are some key characteristics of black box security audits:

• Lack of internal knowledge: The testers have no access to the internal details of the system, such as source code, detailed network architecture, or other sensitive information.
• Simulation of an external attack: The black box approach simulates an attack from an individual outside the organization, such as a malicious hacker.
• Comprehensive evaluation: The testers explore the system exhaustively, trying to identify potential vulnerabilities and security weaknesses with no prior knowledge.
• Realistic methodology: The testers often use realistic attack methodologies, simulating scenarios that real attackers could also use.
• Reduced false positives: Due to the lack of prior information, the results of black box security audits tend to reduce false positives, as the vulnerabilities identified are often those that can be exploited without internal knowledge.

A grey box security audit, also known as a grey box penetration test, is an intermediate approach between black box and white box security audits. These terms refer to the amount of prior information that testers have about the system being audited. Thus, in a grey box security audit, testers have an intermediate view of the system. This allows them to simulate an attack with a higher level of knowledge than a black box approach, which can be more realistic, while avoiding the potential risks associated with complete knowledge of the system, as is the case with a white box approach.

Grey box security audits offer a balance between realism and security. They allow testers to better target their efforts while evaluating the system’s defenses in more depth than a black box approach. However, they can still simulate the experience of an external attacker who only has a certain level of information.

A white box security audit, also known as a white box penetration test, is an approach where the testers have a thorough and complete knowledge of the infrastructure, source code, and architecture of the system being audited. In other words, the testers have full access to the internal information of the system before starting the audit process.

Here are some of the key characteristics of white box security audits:

• Full access to information: The testers have full access to the technical details of the system, such as the source code, documentation, network architecture diagrams, etc. This detailed information allows the testers to fully understand the internal workings of the system.
• Similar to the perspective of an insider: This approach simulates a situation where an attacker would have a high level of access to information, similar to that of an internal employee or developer.
• In-depth identification of vulnerabilities: With a thorough knowledge of the system, the testers can focus on specific aspects to identify potential vulnerabilities. This may include source code analysis, configuration testing, architecture design assessments, etc.
• Better simulation of a targeted attack: Since the testers have prior knowledge of the system, they can simulate more targeted and sophisticated attacks, similar to those that a well-informed attacker could undertake.
• Maximization of test coverage: Full access to technical details allows the testers to maximize test coverage, ensuring that they examine all aspects of the system, from application layers to network components to security configurations.