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What is a Brute-Force Attack?

In the world of cybersecurity, a brute-force attack can be devastating for businesses and individuals who have access to sensitive information. Here, we’ll explain what constitutes a brute-force attack on the internet, the motives behind these attacks, and how to prevent them.

What is a Brute Force Attack?

In a brute-force attack, cybercriminals use trial-and-error methods, along with automation, to test vast amounts of password combinations until they are able to access the target's account or system. This method is simple but effective and requires less skill than other, more sophisticated hacking methods. Brute-force attacks work only when the verification system is "something you know," such as a password, personal identification number (PIN), or personal security question. Once attackers gain access to a user account or network, they may steal sensitive data, install malware, or even shut down an entire system.

What are the Motives Behind Brute-Force Attacks?

Bruteforcing often has various objectives. Stealing sensitive information, spreading malware, and disrupting normal services are among the possible motives. Attackers can use brute-force attacks to steal personal or activity data from organizations, causing financial and reputational damage. For instance, if attackers gain access to sensitive data such as customer and employee information, they can use it for illegal activities such as identity theft. They will also target companies with attacks that infest their websites and systems with offensive content, causing reputational damage.

Because there is so much to gain, the bad actors who plan and carry out these attacks spend a large amount of time and money on them. It may take several months or years for an attacker to crack passwords or encryption keys using a brute-force attack.

1. Exploit Ads or Activity Data

Brute-force attacks are often perpetrated with the goal of exploiting ads and activity data for financial benefit. Attackers may place spam ads on popular websites, reroute traffic to illegal sites, and infect websites with malware to collect user data. In addition to these monetary motives, brute-force attacks may also be used to test network security and the strength of encryption protocols used by businesses and organizations.

2. Steal Personal Data

While the motives behind brute-force attacks can vary, in most cases, the primary goal is to steal personal data such as passwords, passphrases, usernames, and PINs. With this information, an attacker can gain unauthorized access to sensitive information, such as bank accounts or personal files, for fraudulent purposes or to cause harm. It's important for individuals and organizations to implement strong security measures, such as two-factor authentication and complex passwords, to protect against brute-force attacks and safeguard their personal information.

3. Spread Malware

Attackers use malware to gain control of a target's system, and then use it as a launching point for wider attacks against other connected networks or systems. In some cases, spreading malware is simply a way for hackers to showcase their hacking skills and play around with them. Regardless of the motive, the use of brute-force attacks to spread malware can have serious consequences for individuals and businesses alike.

4. Hijack Systems for Malicious Activity

Cybercriminals use brute-force attacks with the primary motive of hijacking systems for malicious activities. For instance, they can hijack a group of machines to launch a distributed denial-of-service (DDoS) attack with the intent to overload or crash a target's security and system. Botnets, which are networks of compromised computers, can also be utilized to speed up malicious activity.

5. Ruin a Company or Website’s Reputation

The motive behind brute-force attacks can vary depending on the attacker's goal. In some cases, attackers use brute-force attacks to gain access to sensitive information that they can use for malicious purposes. However, attackers can also use brute-force to damage a company's or website's reputation by altering confidential information that goes against its core values. This can include defacing websites, leaking confidential data, or spreading false information online.

Types of Brute-Force Attacks

There are several types of brute-force attacks. Each has its own strengths and weaknesses, and understanding them can help individuals and organizations better protect themselves against brute-force attacks. It is crucial to note that protecting sensitive information with strong, unique passwords is essential to prevent these types of attacks.

1. Simple brute-force attacks

Simple brute-force attacks try all possible combinations of possible passwords from a given character set. They use automated software to test large quantities of possible combinations in order to decode passwords, PINs and other forms of login data.

2. Dictionary attacks

One common type of brute-force attack is the dictionary attack. With this approach, an attacker attempts to crack a password-protected security system by using a list -- or dictionary -- of common words and phrases. It can be a time-consuming process, and success rates are typically low. But the attack is popular because many people reuse common or weak passwords, making it easy for hackers to exploit these vulnerabilities and get into user accounts.

3. Hybrid brute-force attacks

The hybrid brute-force attack combines elements of both simple brute-force and dictionary attacks to increase the likelihood of success, such as modifying words in a dictionary by adding numbers or changing the letter case.

4. Credential stuffing

With credential stuffing, an attacker gains entry by using known, valid credentials that have been exposed in data breaches. The attacker then tries these credentials across multiple systems to see if they work. Credential stuffing can be extremely effective, as many people use the same username and password across multiple accounts.

5. Reverse brute-force attacks

In a reverse brute-force attack, the attacker uses a known password with various usernames or encrypted files to get network access. This method works because many users have common passwords, such as "password" or “123456.” Attackers may be able to guess usernames by having a list of employee names and knowing an organization's standardized email format for usernames.

What is a Strong Password?

A strong password is significantly less susceptible to a brute-force attack. According to Cybernews, a strong password has the following characteristics:

  • Is at least 12 characters long. The longer the better.
  • Uses uppercase and lowercase letters, numbers and special symbols.
  • Doesn't contain memorable keyboard paths.
  • Is not based on your personal information.
  • Passwords are unique for each account.
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How Do You Prevent a Brute-Force Attack?

There are a number of ways to prevent a brute-force attack, and a combination of tactics is needed, but the most important factor is strong, unique passwords.

Password Strength Chart

Enabling multi-factor authentication (MFA) and creating unique passwords for each service can significantly reduce the risk of password hacking.

It is also beneficial to use software that automatically locks out IP addresses that have generated too many failed logins. Hackers use software to randomly try different passwords, so using longer passwords and more complex passwords with special characters will help protect against brute-force attacks. Consider using a password manager to generate and store complex passwords securely. Users also should avoid entering passwords or personal information into web applications that do not protect their data with strong encryption keys.

Lock Accounts

Locking accounts after a predetermined number of unsuccessful password tries is a straightforward method of preventing brute-force attacks. A drawback to this approach is that it is easy for someone to exploit this security feature and lock out hundreds of user accounts. In fact, some websites are targeted so frequently that they cannot implement a lockout policy since they would have to be unlocking user accounts all the time.

Inject Random Pauses

Inserting random pauses when checking a password is a simple fix because the attack's success depends on time. Even a brief interruption can significantly slow down a brute-force attack, but most legitimate users won't notice this delay. However, if the attacker submits numerous simultaneous authentication requests, imposing a delay will have less of an impact.

Ask Secret Questions

A system could prompt the user to answer a secret question—in addition to the username and password—after one or two unsuccessful login attempts. This makes it hard for automated attacks to work and makes it impossible for an attacker to get in, even if they know the account name and password.


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Brute force attacks are serious cybersecurity risks that leave your data unprotected. By being aware of the various types of brute force attacks and patterns adopted by hackers, it is possible to preempt and evade these attacks. Businesses should prioritize the importance of password hygiene and take necessary measures to prevent password hacking. This can be done by creating strong passwords, limiting the number of login attempts and deploying a modern CAPTCHA solution like MatchKey.

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