Pentesting

Cybersecurity's importance is growing rapidly as it affects nearly every aspect of modern life. From individuals needing strong password policies to secure their emails to organizations protecting devices and sensitive data, the need for robust security measures is clear. Headlines frequently report on hacks and data breaches, underscoring the pervasive risks.

One vital aspect of cybersecurity is penetration testing (or pentesting), an ethical process designed to evaluate the security of systems.

Pentesting involves using the same tools and techniques that malicious attackers would employ to identify and fix vulnerabilities, serving as a proactive audit of an organization's defenses.

According to Security Magazine, a cybersecurity industry magazine, there are over 2,200 cyber attacks every day - 1 attack every 39 seconds. [Ref: THM]

What it is?

  • Controlled Attack Simulation: It mimics the techniques of real attackers to assess the strength of security defenses.

  • Risk Identification: It identifies and reports security weaknesses, allowing organizations to address them.

  • Ethical and Authorized: Pentesters work with permission and within legal and ethical guidelines.

  • Part of a Security Audit: It’s typically a part of a broader security assessment to measure an organization's resilience against cyber threats.

What it isn't?

  • Pentesting uncovers vulnerabilities, but it does not fix them. The organization needs to apply the recommended fixes.

  • Security threats evolve, so pentests should be performed regularly, not just once.

  • Unlike malicious hacking, pentesting follows strict rules and is conducted with authorization.

  • Pentesting goes beyond automated scanning tools by providing real-world exploitation scenarios, manual testing, and strategic thinking that scanners cannot achieve.

Methodologies

Penetration tests can have different goals and targets, so no two tests are exactly alike. There isn't a single way to approach them. The process a penetration tester follows is called the methodology, and it should be tailored to fit the specific situation. For example, a method for testing a web application's security wouldn’t work for testing a network's security.

Before diving into industry-standard methodologies, it’s important to note that they all share a common approach.

Stages

Information Gathering

In this stage, the goal is to gather as much publicly available information about the target or organization as possible, such as through OSINT and research.

Important: This does not include scanning any systems.

There are two types of information-gathering techniques: Active Information Gathering and Passive Information Gathering.

  • Passive Information Gathering involves collecting publicly available data about a target without directly interacting with the system. This includes activities like OSINT research, social media analysis, and reviewing public databases.

  • Active Information Gathering involves more direct interaction with the target system, which may include certain scanning techniques. While scanning itself isn’t part of basic information gathering, active reconnaissance involves communicating with the system to gather details. Active recon serves as a bridge between reconnaissance and enumeration, often providing deeper insights into the system’s structure and defenses.

Enumeration/Scanning

This stage focuses on identifying applications and services operating on a system. For instance, you might discover a web server that could have vulnerabilities.

Examples -

  • Identifying open ports on a network using tools like Nmap

  • Retrieving user account details or shared resources on a system

  • Gathering information about services, such as DNS or SMB, to find potential entry points.

Exploitation

This stage involves taking advantage of vulnerabilities found in a system or application. It may include using publicly available exploits or manipulating the application's logic to gain unauthorized access.

For example, exploiting an outdated version of a web application’s content management system (CMS) to gain administrative control.

Maintaining Access/Privilege Escalation

After successfully exploiting a system or application (referred to as gaining a foothold), the next step is to try to extend your access within the system and maintain that access. This can involve horizontal privilege escalation, where you gain access to another account with the same level of permissions (e.g., another user), or vertical privilege escalation, where you gain access to a higher-privileged account (e.g., an administrator). Once access is extended, attackers may also set up backdoors or other mechanisms to maintain persistent access to the system.

For example, using a low-level user account to gain access to an admin account by exploiting a privilege escalation vulnerability and then installing a backdoor to ensure ongoing access even if the vulnerability is patched.

Post-Exploitation

This stage includes several key steps:

  1. Identifying other potential targets within the network (pivoting).

  2. Gathering additional sensitive information from the compromised system now that you have privileged access.

  3. Covering your tracks to avoid detection by clearing logs or removing traces of your activities.

  4. Documenting the process and findings in a report.

Examples:

  • Using pivoting to move laterally within the network and exploit other connected systems.

  • Extracting confidential data like password files or system configurations after gaining administrative access.

  • Deleting logs to erase evidence of your presence before exiting the system.

Last updated