Some of the high risk cyber security attacks do not come from zero-day vulnerabilities or clever code exploits, they stem from sheer persistence. Brute force attacks are a great example for this. Unlike more technical strategies, these attacks do not depend on flaws within systems or websites. Instead, they exploit one of the fragile links in the security chain: Human credentials.

According to a recent Verizon report in 2024, 77% of attacks against web applications were caused by stolen credentials or brute force attacks. As more businesses transition towards cloud based operations, there is an increase in volume of digital assets from login portal to encryption data stay online. Any resource that is secured by password, SSH Logins, API keys, and encrypted database becomes prime target.

This is why it is important for security teams to understand how brute force attacks work and enforce strict measures to defend against them. This blog explores what is brute force attacks and provides best ways for security teams to prevent them.

What is a Brute Force Attack?

Bruce force attack is type of cybersecurity attack that uses hacking method by trial and error to crack login credentials, encryption keys or other sensitive data. Cyber attackers test various combinations systematically until they find the right one, and they also use automated tools for efficiency. This method requires computational ability than any advanced techniques, which is commonly used to guess weak passwords or get unauthorized access to systems.

5 Types Of Brute Force Attacks

There are various types of brute force attacks that lets cyber attackers gain unauthorized access and steal user data. Here’s a breakdown of common types of brute force attacks:

Simple Brute Force Attack

A simple brute force attack is systematically trying all the combinations of numbers, characters, and special characters to crack a password. This method is quiet straightforward, but a can be bit of time consuming for strong passwords. Cyber attackers utilize automated tools to make the process faster and more efficient than manual attempts.

This type of brute force attack works well for weak passwords and short passwords. However, they become ineffective for strong passwords because of vast number of possible challenging combinations.

Dictionary Attack

In dictionary attacks, attackers use a list of words from dictionary along with common variations like adding special characters or numbers to guess passwords. This type of attack is much effective than simple brute force, where attackers can quickly test common words and their variations, like adding “1“ or “!” to end of words.

It can also be executed faster than simple brute force attack, as it focuses on most commonly used phrases and words. This makes it easier to guess passwords that is based on everyday lingo. Dictionary attacks can be easy if the users choose passwords that easily guessable from the list of common used words.

Hybrid Brute Force Attack

Hybrid brute force attacks is a type of attack that combines some elements of dictionary attacks and traditional brute force methods. Cyber attacker start with common words and then add variations from the dictionary such like numbers, special characters to increase the chance of cracking the passwords. Ex: “SanFrancisco123” or “Riverdale2020”. This strategy balances effectiveness of dictionary attacks with extensiveness brute force.

Through this hybrid attacks can quickly guess passwords based on common words with basic variations. This method is efficient for common passwords and it provides balance between speed and comprehensiveness, which makes it a versatile tool for attackers.

Reverse Brute Force Attack

In a reverse brute force attack, cyber attackers start with known password and then try it against various usernames until they find a match. This method is effective when attackers have list of commonly used passwords. Attackers can quickly find valid credentials without the need to guess them from scratch.

Reverse brute attacks perform well when users keep reusing the common passwords across different accounts, which makes it easier for attackers to find match. This approach is faster for large userbases, as it uses the probability of password reuse to get unauthorized access.

Credential Stuffing

In credential stuffing, cyber attackers take stolen username and password combinations are used from one system and access other systems. This method depends on users who reuse passwords across various accounts. Credential stuffing is effective because many users reuse passwords, which makes it probable that some stolen credentials could work elsewhere.

This approach is quick and efficient and eliminates the requirement to guess passwords from the start. Also it helps attackers to quickly identify valid login credentials without using time consuming brute force methods.

How Does Brute Force Attacks Work?

Source: Certera

• Target Selection: The cyber attacker identifies target system, account or encryption method. The target could be a user account on website, encrypted file or a management portal.

• Determining Credentials: Next, the cyber attacker evaluates the format and requirements for credential authentication. For instance, they determine character set and length (eg., special characters, alphanumeric) of passwords.

• Execution of Attack: Using automated tools or scripts, the attacker generates and tests various combinations of credentials. These tools can rapidly input thousands of guesses per second into the login interface of the target system.

• Analyzing Response: The cyber attacker monitors server responses to check whether access has been granted. A successful login indicates that the correct credentials have been guessed.

• Exploitation: After access is gained, attackers may steal sensitive information, install malware, escalate privileges within a network, or cause other disruptions depending on their objectives

Examples of Brute Force Attacks

According to a recent report there’s an increase of 400% brute force attacks by attackers, that targeted RDP’s during remote work setups worldwide to gain unauthorized access. This rise in number and examples emphasize the importance of enforcing strict security measures. Below examples highlights widespread impact of brute force attacks across platforms and industries:

T-Mobile Data Breach - 2021

In 2021, T-Mobile experienced a major data breach that exposed personal information of around 40 million customers. Attackers combined brute force methods with other techniques to get access to T-Mobile’s systems, and also exploited vulnerabilities in infrastructure which easily allowed access to confidential data like name, address and security numbers.

Firefox Master Password Vulnerability - 2019

Firefox’s master password mechanism was prone to brute force attacks due to its dependence on the old SHA-1 hashtag algorithm. Attackers exploited this weakness until the time Mozilla patched it in the year 2019, this was after 9 years after the vulnerability.

Magento Admin Panels Bruce Force Attacks - 2018

In 2018, Magento a well known e-commerce platform, faced severe brute force attacks that targeted its admin panels. Attackers attempted to guess weak passwords used by managers and were successfully able to compromise almost 1000 admin panels. It also let attackers to install malware on affected sites, steal customer data and manipulate product listings.

These above examples emphasize the importance of enforcing strict security measures

Best Ways to Prevent a Brute Force Attack

Implementing the below practices can majorly reduce the risk of brute force attacks:

Use Strong Passwords Mandatorily

Mandatorily create extremely complex and long passwords of at least 15 characters with mix of lowercase, uppercase, symbols and numbers. Avoid personal information or dictionary words. Make sure that each account has unique or difficult password to prevent credential stealing.

Set Limits to Login Attempts

Set a limit for maximum number of failed login attempts before choosing account lock. Make use timers or set additional verification requirements for repeated failed attempts to prevent automated brute force tools.

Enforce Multi Factor Authentication (MFA)

Include extra layer of security by a enabling multifactor like one time password (OTP) , hardware token or biometric scan. Attackers can guess primary passwords but cannot bypass Multi factor authentication, so it is important to mandatorily enforce it.

Implement CAPTCHA

Include CAPTCHA challenges on login pages to differentiate between real human and bots. CAPTCHA can properly restrict brute force attacks carried out by bots and scripts.

Restrict IP Addresses

Monitor login activities and restrict suspicious IP addresses and ranges. Make sure to whitelist trusted and genuine IP addresses for sensitive vulnerable systems and admin interfaces to prevent access from unauthorized sources.

Implement Web Application Firewalls

Implement WAF’s to monitor and filter traffic to your web applications. WAF’s can help identify and block brute force attempts by restricting number of requests from single source within specified time frame.

Regularly Update Software

Regularly update software, that includes applications and operating systems with latest security patches. Update mostly address vulnerabilities and threats that attackers could exploit in brute force attempts.

Final Thoughts

By implementing the above best practices, security teams can build a strong defense system. Secure your API’s from brute force attacks with Akto’s comprehensive security platform. Akto provides over 400 built-in case studies that target vulnerabilities like credential stuffing, user enumeration, session management flaws, and CAPTCHA bypass. Its continuous monitoring and automated token handling ensures authentication flows are accurately and rigorously tested, which improves API’s resilience against unauthorized access.

Book a demo today to see akto in action and learn about more features.!