What is a Brute Force Attack?

A brute force attack is a method of hacking that involves systematically attempting various combinations of passwords, login credentials, and encryption keys until the correct ones are identified. This straightforward approach is effective for gaining unauthorized entry into individual accounts and the systems and networks of organizations. Attackers use automated tools to cycle through numerous username and password combinations until they discover the correct login details.

The term “brute force” originates from attackers employing relentless and forceful techniques to penetrate user accounts. Despite its age, brute force attacks persist as a favored strategy among hackers due to their proven track record of success.

Reasons Behind Brute Force Attacks

Hackers are aware that most users use weak passwords, which are typically short and simple, lacking a mix of uppercase letters, lowercase letters, numbers, and special characters to enhance complexity. Furthermore, many account credentials include personal details that can be easily obtained online, such as a user’s name, birthdate, or interests. For instance, if a hacker discovers from a LinkedIn profile that someone works in a specific industry and frequently attends conferences related to that field, they could incorporate this information into their brute force algorithms.

Upon gaining access to a system, the hacker can exploit this opportunity to steal proprietary information for a competitor, download data for sale on the dark web, lock out administrators until a ransom is paid, or introduce malware into the system for economic, political, or social reasons.

How Do Brute Force Attacks Work?

A brute force attack is both a specific method of attack and a broad category encompassing similar techniques, with variations in where hackers begin and how they execute their attempts. As previously mentioned, hackers may employ manual processes or automated software to breach a private network. Additionally, hackers might possess certain information before initiating their attacks.

For instance, in a method known as “reverse brute force attacks,” hackers already possess a list of brute-force passwords obtained from the dark web and seek to match them with a username for access. Alternatively, in another type called “credential stuffing,” hackers already have the correct credentials for one website, user account, or system and try to use them on others.

Different Types of Brute Force Attacks

Within the broader scope of brute force attacks, there exists a range of methodologies with slight variations in how they are executed. The primary types of brute force attacks are:

• Traditional Brute Force Attacks: This straightforward method involves a hacker having a username or list of usernames and then attempting, either manually or through a brute force program script, to guess passwords until they find the correct combination of credentials.
• Dictionary Attacks: An advanced technique where a hacker utilizes a precompiled list of phrases based on research about the target or variations of common passwords to test against a specific username. The chosen list is often referred to as a “dictionary” containing modified or slightly altered words or character combinations.
• Hybrid Attacks: This method combines traditional brute force attacks with dictionary attacks. The hacker selects the most commonly used phrases and words from the dictionary and then tries various permutations of potential passwords until they find a valid combination.
• Reverse Brute Force Attacks: In this approach, a hacker begins with a known password, obtained from a breach or commonly used, and then attempts numerous usernames until a match is found. Unlike traditional brute force or dictionary attacks, this method works backward, starting with known passwords instead of usernames.
• Credential Stuffing: This technique involves a hacker already possessing known username and password combinations for one system and utilizing those same credentials to access other accounts, profiles, or systems associated with the same user. This attack is successful because users frequently reuse passwords across multiple accounts.

Popular Brute Force Attack Tools

The most prevalent brute force attack tools are those designed to automate the process of guessing credentials and discovering combinations. These tools serve various functions, including identifying weak passwords, decrypting password data, generating character combinations, and executing dictionary attacks across numerous protocols and operating systems.

Some of the most widely used tools include:

• John the Ripper: This open-source software enables users to conduct dictionary attacks and detect weak passwords through diverse cracking and decryption methods.
• Aircrack-ng: An open-source tool primarily focused on penetration testing for wireless network security, utilizing dictionary attacks against network protocols.
• Hashcat: A penetration testing platform that allows hackers to utilize known “hashes,” which are passwords processed through a formula and converted into a string of random characters of consistent length regardless of the password’s complexity. With access to the hashes, Hashcat facilitates dictionary or rainbow table attacks to reverse the password into readable text.

Difference Between Online and Offline Brute Force Attacks

In online brute force attacks, the hacker focuses directly on the network or application. However, these attacks are hindered by the countermeasures implemented by the system. For example, most systems will lock out a user after a certain number of incorrect login attempts.

To circumvent this obstacle, attackers resort to offline brute force attacks. These attacks allow for password cracking attempts without accessing the user’s server. Since password data is typically hashed or encrypted for security, hackers reverse their approach in offline attacks by using known hashes and employing computer programs to match them with known passwords until a correct combination is discovered.

How to Prevent Brute Force Attacks

Both individuals and organizations have various strategies at their disposal to defend against known vulnerabilities such as Remote Desktop Protocol (RDP). Additionally, the study of ciphers and cryptography, known as cryptanalysis, can empower organizations to enhance their security measures and shield their sensitive information from brute force attacks.

Use stronger password practices

The most effective defense against brute force attacks targeting passwords is to create highly resilient passwords. Both end-users and organizations have a crucial role in safeguarding their data by employing robust passwords and adhering to strict password security practices. Strengthening passwords can significantly increase the complexity and time required for attackers to crack them, potentially leading them to abandon their efforts.

Recommended practices for creating stronger passwords include:

• Generate strong, multi-character passwords: It’s advisable to create passwords that exceed 10 characters and incorporate a mix of uppercase and lowercase letters, symbols, and numbers. This significantly raises the difficulty level, making it more challenging and time-consuming for hackers to decipher passwords, particularly without access to powerful computing resources.
• Utilize complex passphrases: While longer passwords are generally more secure, certain websites may impose restrictions on password length. In such cases, employing complex passphrases can thwart attackers attempting simple dictionary attacks. Passphrases consist of multiple words or segments combined with special characters to enhance security.
• Implement password-building rules: Another effective tactic is to obfuscate words to render them unintelligible to unauthorized individuals. This can involve truncating words by removing vowels or utilizing abbreviated versions of words to construct a coherent phrase. For example, transforming “hope” into “hp” or “blue” into “bl.”
• Steer clear of common passwords: Avoid using easily guessable passwords, such as common names, sports teams, or the word “password” itself. Hackers often exploit knowledge of frequently used words or phrases in their attempts to compromise accounts.
• Employ unique passwords for each account: Avoid the risk of credential stuffing attacks by refraining from reusing passwords across multiple websites or accounts. Hackers exploit this practice by testing passwords obtained from one website on others where the same credentials might be used.
• Leverage password managers: Password managers streamline the process of generating secure, unique passwords for various websites. They automatically create and manage login credentials for multiple accounts, allowing users to access their accounts by logging into the password manager. With a password manager, users can generate long, complex passwords, securely store them, and mitigate the risk of forgetting or losing passwords.

By implementing these practices, individuals and organizations can significantly bolster their defenses against brute force attacks and enhance the security of their sensitive data.

Better protect user passwords

Following strong password best practices is of limited benefit if an organization fails to safeguard its data from brute force attacks. It is incumbent upon the organization to protect its users and enhance network security through various tactics:

• Employ high encryption rates: Utilizing the highest available encryption rates, such as 256-bit encryption, when encrypting system passwords significantly reduces the likelihood of a successful brute force attack and increases password resilience.
• Salt the hash: Salting the hash is a cryptographic technique employed by system administrators to reinforce password hashes. This involves adding a unique salt—composed of random letters and numbers stored separately in a database—to each password, thereby enhancing its security.
• Implement multi-factor authentication (MFA): MFA diminishes reliance on passwords by requiring additional verification steps during user login. After entering their password, users must provide supplementary proof of identity, such as a code sent via SMS, a fingerprint scan, or authentication through a secondary device, reducing the risk of unauthorized access.
• Restrict login attempts: Limiting the number of login attempts a user can make mitigates the success rate of brute force attacks. Implementing restrictions, such as locking out users after a few unsuccessful login attempts or completely suspending account access following multiple failures, deters potential attackers from repeatedly testing username and password combinations.
• Employ CAPTCHA for login support: Integrating CAPTCHA challenges into the login process helps thwart automated brute force attacks by requiring users to complete additional verification tasks, such as typing text from images, checking boxes, or identifying objects.
• Utilize an Internet Protocol (IP) blacklist: Maintaining a blacklist of IP addresses associated with malicious activities aids in safeguarding the organization’s network and users from known attackers. Regularly updating the blacklist is crucial to prevent new attack vectors.
• Remove unused accounts: Inactive or unmanaged accounts pose a security risk and provide avenues for cybercriminals to exploit. Organizations should regularly audit and eliminate unused accounts, particularly those with elevated permissions or access to sensitive corporate data, to mitigate the risk of brute force attacks.

By implementing these measures, organizations can enhance their resilience against brute force attacks and protect their data and users more effectively.

Provide ongoing security and password support

In addition to promoting user awareness and maintaining robust IT security measures, businesses must prioritize the consistent updating and support of systems and software.

• Offer password education: Users should be equipped with knowledge about effective security practices and password usage. It’s crucial for them to understand the indicators of cyberattacks and receive regular training and updates to stay informed about evolving threats and reinforce good habits. Corporate password manager tools or vaults can assist users in storing complex passwords securely, reducing the risk of password loss and potential compromise of corporate data.
• Implement real-time network monitoring: Detecting brute force attacks requires vigilance for telltale signs such as numerous login attempts or access from unfamiliar devices or locations. Businesses should continually monitor their systems and networks for any suspicious or anomalous activities and promptly intervene to block potentially malicious behavior.

FAQ’s

What is a brute force attack?

A brute force attack is a method of hacking where attackers systematically attempt various combinations of passwords, login credentials, or encryption keys until the correct ones are found, enabling unauthorized access to accounts, systems, or networks.

Why do brute force attacks persist as a favored strategy among hackers?

Brute force attacks remain popular due to their simplicity and effectiveness in penetrating user accounts and organizational systems. Despite advancements in cybersecurity, many users still utilize weak passwords or reuse them across multiple accounts, making them vulnerable to such attacks.

How do hackers exploit personal information in brute force attacks?

Hackers leverage personal information, such as names, birthdates, or interests, to enhance the effectiveness of brute force algorithms. By incorporating this information, attackers can increase the likelihood of guessing correct passwords, especially if users use easily guessable or commonly used passwords.

What are some common types of brute force attacks?

Common types of brute force attacks include traditional brute force attacks, dictionary attacks, hybrid attacks, reverse brute force attacks, and credential stuffing. Each type varies in methodology but shares the objective of gaining unauthorized access through exhaustive password guessing.

What are some popular tools used in brute force attacks?

Popular tools for brute force attacks include John the Ripper, Aircrack-ng, and Hashcat. These tools automate the process of guessing credentials and discovering password combinations, facilitating unauthorized access to accounts or systems.

How do online and offline brute force attacks differ?

Online brute force attacks target network or application login interfaces directly but are hindered by system countermeasures, such as account lockouts. In contrast, offline brute force attacks involve password cracking attempts without accessing the user’s server, typically using known hashes and computer programs to match them with passwords.

What measures can individuals and organizations take to defend against brute force attacks?

To defend against brute force attacks, individuals and organizations should implement strong password practices, utilize encryption, employ multi-factor authentication, restrict login attempts, use CAPTCHA for login support, maintain IP blacklists, remove unused accounts, provide ongoing security education, and implement real-time network monitoring.

How can businesses support users in creating and managing strong passwords?

Businesses can provide password education to users, promoting awareness of security best practices and the importance of using complex passwords. Additionally, they can offer corporate password manager tools or vaults to assist users in generating, storing, and managing secure passwords effectively.

Conclusion

Brute force attacks remain a persistent threat due to their simplicity and effectiveness. To mitigate these risks, both individuals and organizations must prioritize strong password practices, encryption, multi-factor authentication, and real-time network monitoring. By implementing these measures, businesses can better protect their data and networks from unauthorized access.