How Hackers Break Into Companies and How to Prevent It

In recent years, cyberattacks have ceased to be a distant problem, limited to large global corporations, and have come to affect businesses of all sizes. In Brazil, cases of ransomware, breaches of internal systems, and digital fraud are now part of the daily routine for small and medium-sized businesses. Often, an attack begins with a simple malicious email and can result in the complete shutdown of operations.

But how, exactly, does a hacker manage to break into a company? To understand how to protect yourself, you need to understand the anatomy of a cyberattack: the steps involved, the most common techniques, and the vulnerabilities that are exploited.

What is a cyberattack?

A cyberattack is any malicious act carried out through computers, networks, or systems, with the aim of stealing information, disrupting services, or obtaining financial gain.

Among the most common types are:

• Phishing: fake messages that trick users into clicking on malicious links or providing passwords;
• Ransomware: data hijacking with demands for ransom in cryptocurrency;
• DDoS (denial of service): intentionally overloading servers to take systems offline;
• Social engineering: the psychological manipulation of employees to gain access to internal information.

These attacks don't happen by chance: they follow a pattern, almost like a "step-by-step" process.

Stages of a Cyberattack

1. Reconnaissance (Initial Surveillance)

Before launching an attack, criminals need to know their target. They search for publicly available information on websites, social media, and even LinkedIn to find out:

• Who are the company's employees?;
• What software or systems are in use;
• Potential vulnerabilities in websites or applications.

A simple post by an employee can provide valuable clues, such as “we’re implementing a new ERP system.” This could tip off attackers as to which system to target.

2. Exploiting Vulnerabilities

With this information in hand, hackers look for technical vulnerabilities. These may include:

• Weak or reused passwords;
• Outdated systems without security patches;
• Two-step authentication is missing.

A classic example is the WannaCry ransomware attack (2017), which exploited a vulnerability in Windows systems that had not received the security update.

3. Access Gain

This is where the actual intrusion begins. The hacker can:

• Send an email with a fake link to steal credentials;
• Use malicious software to gain access to the network;
• Use passwords obtained from previous data breaches.

Often, simply clicking on an infected attachment is enough to open the “backdoor.”

4. Elevation of Privileges

Gaining access to a regular account may not be enough. That’s why hackers try to elevate their privileges to access more sensitive data.
Example: An attacker who logged in as a “standard user” may try to elevate their privileges to “administrator” and thus gain full control of the systems.

5. Lateral movement

Once inside the network, hackers move from machine to machine, exploiting internal connections until they reach the most valuable areas: file servers, financial systems, and customer databases.

This type of attack is usually silent. Many companies don't realize they've been attacked until it's already too late.

6. Data extraction or encryption

At this stage, the criminals carry out their main objective:

• Stealing information (customer data, contracts, passwords, intellectual property);
• Encrypt data and demand a ransom (as in the case of ransomware).

A recent example was the attack on Colonial Pipeline (U.S., 2021), in which criminals shut down one of the country’s largest oil pipelines and only released it after receiving millions in cryptocurrency.

7. Access Maintenance

Finally, many hackers install “backdoors”—hidden entry points that allow them to return to the system in the future, even if the main intrusion is discovered. It’s as if they were leaving a spare key hidden under the rug.

Real-life examples:

• WannaCry (2017): affected more than 200,000 computers in 150 countries by exploiting vulnerabilities in unpatched systems;

• Colonial Pipeline (2021): a ransomware attack that disrupted fuel supplies in the U.S.;
• Brazilian cases: In 2020 and 2021, major telecommunications and healthcare companies had their systems brought to a standstill by ransomware, resulting in millions in losses.

These cases show that the weakest link can be either technical or human.

Read more at: cybersecurity-with-multi-layered-protection

How to Prevent It: Practical Strategies for Businesses

The good news is that, by understanding the mechanics of the attack, it's also possible to understand how to defend against it.

1. Awareness and Training

Employees are the first line of defense. It is essential to train teams to recognize suspicious emails, avoid sharing passwords, and adopt safe digital habits.

2. Security Policies

Establishing clear rules for device use, remote access, and data storage is essential. Companies without defined policies become easier targets.

3. Technical safeguards

• Advanced firewalls and antivirus software;
• EDR (Endpoint Detection & Response) solutions for monitoring suspicious activity;
• Multi-factor authentication;
• Regular software updates.

4. Immutable backup and disaster recovery

One of the most common mistakes is relying solely on “traditional” backups. In the case of ransomware, even backups can be encrypted.
With immutable backups, data is protected against changes, ensuring recovery even after an attack.

5. Continuous monitoring

Having a security team or partner that monitors the network 24/7 makes it possible to identify signs of an attack early on, before they spread.

6. Tests and simulations

Simulating phishing attacks and conducting penetration tests (pentests) help identify vulnerabilities before cybercriminals do.

Conclusion: Prevention is the best investment

A cyberattack is not a one-time event, but a process with several well-defined stages. Understanding this process is the first step toward protecting your company.

Each stage—from detection to maintaining access—offers opportunities for defense. With awareness, the right technology, and prevention strategies, it is possible to drastically reduce the risks.

The key lesson is simple: prevention is much more affordable and effective than cure. Investing in cybersecurity isn’t an expense—it’s a way to protect your reputation, customer trust, and business continuity. Learn more!

Written byCaroline Peres OrtegaMarketing Analyst — ADD IT Cloud Solutions

Responsible for the editorial content at ADD IT Cloud Solutions, he produces articles and materials on private cloud, cybersecurity, disaster recovery, and digital transformation for the Brazilian B2B market. He monitors trends in the cloud computing industry and translates complex technical topics into strategic content for IT professionals and decision-makers.

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