How Hackers Break into Companies and How to Prevent It

In recent years, cyber attacks have ceased to be a distant problem, restricted to large global corporations, and have started to affect companies of all sizes. In Brazil, cases of data hijacking (ransomware), intrusions into internal systems and digital fraud are already part of the routine for small and medium-sized companies. Often, the attack starts with a simple malicious email and can end with a complete shutdown of operations.

But how, after all, does a hacker manage to break into a company? To understand how to protect yourself, you need to know the anatomy of a cyber attack: the stages, the most common techniques and the weak points that are exploited.

What is a cyber attack?

A cyber attack is any malicious action carried out through computers, networks or systems, with the aim of stealing information, interrupting services or obtaining financial gain.

Among the most common types are

• Phishing: fake messages that induce the user to click on malicious links or provide passwords;
• Ransomware: data hijacking with a cryptocurrency ransom demand;
• DDoS (denial of service): deliberately overloading servers to take systems offline;
• Social engineering: psychological manipulation of employees to gain access to internal information.

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

Stages of a cyber attack

1. Reconnaissance (initial spying)

Before attacking, criminals need to know their target. They search for public information on websites, social networks and even LinkedIn to find out:

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

A simple post by an employee can give valuable clues, such as "we are implementing a new ERP". This can tell attackers which system to target.

2. Exploitation of vulnerabilities

With the information in hand, hackers look for technical flaws. This can include:

• Weak or reused passwords;
• Outdated systems without security patches;
• Lack of two-step authentication.

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

3. Gaining access

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

• Sending an email with a fake link to steal credentials;
• Using malicious software to enter the network;
• Use passwords obtained in previous leaks.

Often, a simple click on an infected attachment opens the "gateway".

4. Escalating privileges

Being able to access an ordinary account may not be enough. That's why hackers try to increase their privileges in order to get to more sensitive data.
For example, an attacker who has logged in as a "standard user" may try to turn himself into an "administrator" and thus have full control of the systems.

5. Lateral movement

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

This movement is usually silent. Many companies only realize the attack when it's too late.

6. Data extraction or encryption

At this stage, the criminals put their main objective into practice:

• Stealing information (customer data, contracts, passwords, intellectual property);
• Encrypting data and demanding a ransom (ransomware).

A recent example was the attack on the Colonial Pipeline (USA, 2021), in which criminals paralyzed one of the country's largest oil pipelines and only released it after paying millions in cryptocurrencies.

7. Access maintenance

Finally, many hackers install "backdoors" - hidden doors that allow them to return to the system in the future, even if the main invasion is discovered. It's as if they left an extra key hidden under the mat.

Real examples:

• WannaCry (2017): affected more than 200,000 computers in 150 countries, exploiting flaws in non-updated systems;

• Colonial Pipeline (2021): ransomware attack that interrupted fuel supplies in the US;
• Brazilian cases: in 2020 and 2021, large telecom and healthcare companies had their systems paralyzed by ransomware, generating millions in losses.

These cases show that the weakest link can be both technical and human.

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

How to prevent it: practical strategies for companies

The good news is that by knowing the anatomy of the attack, you can also understand how to defend yourself.

1. Awareness and training

Employees are the first line of defense. It is essential to train teams to recognize suspicious emails, not share passwords and adopt safe digital habits.

2. Security policies

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

3. Technical protections

• Advanced firewalls and antivirus;
• EDR (Endpoint Detection & Response) solutions to monitor suspicious activity;
• Multi-factor authentication;
• Constant updating of software.

4. Immutable backup and disaster recovery

One of the most common mistakes is to only make "traditional" backups. In the case of ransomware, even backups can be encrypted.
With immutable backup, data is protected from alteration, guaranteeing 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 carrying out penetration tests (pentests) help to identify flaws before the criminals do.

Conclusion: prevention is the best investment

A cyber attack is not an isolated event, but a process with several well-defined stages. Understanding this anatomy is the first step to protecting your company.

Every phase, from reconnaissance to maintaining access, offers opportunities for defense. With awareness, appropriate technology and prevention strategies, it is possible to drastically reduce the risks.

The big lesson is simple: prevention is much more affordable and efficient than cure. Investing in cybersecurity is not an expense, it's protection of reputation, customer confidence and business continuity. Find out more!