What is a brute force attack?
A brute force attack is a hacking technique that involves repeatedly trying different combinations of passwords or encryption keys until the correct one is found, often using automation. This method relies on trial and error and is commonly used to gain unauthorized access to systems, networks, and accounts.
Brute force attacks are one of the oldest and most straightforward methods used by cybercriminals, but they remain effective due to the simplicity of execution and the potential rewards. These attacks can target anything from personal accounts to large corporate databases, making them a significant concern in the world of cybersecurity.
How does a brute force attack work?
A brute force attack works by systematically testing manycombinations of characters, numbers, and symbols to guess a password or encryption key. Cybercriminals often automate this process with specialized tools, allowing them to test a vast number of potential passwords in a short time.
Whether a brute force attack is successful depends on the complexity and length of the password or key. Simple, short passwords are much easier to crack, while longer, more complex passwords require far more time and resources to break. Even though the method is basic, brute force attacks can be highly effective if the targeted passwords are weak or if proper security measures are not in place.
Encryption and cryptography in brute force attacks
Brute force attacks can also be used against encryption keys because encryption and cryptography are essential components of cybersecurity. Encryption is the process of converting information into a code to prevent unauthorized access, using algorithms that require a key to decrypt the data. The strength of encryption is typically measured in bits, with 128-bit and 256-bit encryption being the most common.
- 128-bit encryption is generally considered secure, offering 2^128 possible combinations. It would take an enormous amount of time and computational power to crack, making it resistant to brute force attacks.
- 256-bit encryption is even more robust, providing 2^256 possible combinations. This level of encryption is often used for securing highly sensitive information, as it is virtually impossible to break with current technology.
Cryptography, the science of encoding and decoding information, plays a crucial role in protecting data from brute force attacks. Modern cryptographic methods, such as Advanced Encryption Standard (AES), are designed to resist such attacks by creating encryption keys that are exceptionally difficult to guess. However, if passwords or encryption keys are weak, even strong cryptographic algorithms can be compromised.
Motives behind brute force attacks
Cybercriminals use brute force attacks for various malicious purposes, each with significant potential consequences. Understanding these motives can help in recognizing the broader impacts of such attacks.
Exploit ads or activity data
Brute force attacks can be used to gain control over websites or online platforms for financial gain.
- Placing spam ads: Attackers can place unauthorized advertisements on popular websites, earning revenue from each click or view.
- Rerouting traffic: They might redirect legitimate traffic to illegal or commissioned paid ad sites, profiting from increased visitor counts.
- Infecting with malware: By injecting malicious scripts into compromised sites, attackers can infect visitors with information stealers that are used to collect user data, which is then sold to advertisers without the user’s consent.
Hijacking systems for broader attacks
Brute force attacks are often part of a larger strategy to control multiple systems, for example to form a botnet. A botnet is a network of compromised devices or accounts that cybercriminals can use for various malicious activities, including launching a disinformation campaign or Distributed Denial-of-Service (DDoS) attacks, which overwhelm a target’s systems with a flood of traffic, leading to system crashes or outages.
Ruining a company’s reputation
By successfully executing a brute force attack, cybercriminals can cause severe reputational damage to organizations.
- Data theft: Stealing sensitive data, which, when leaked, can lead to financial loss and loss of customer trust.
- Defacement: Injecting obscene or offensive material into a company’s digital assets, potentially leading to public backlash or legal consequences.
How dangerous is a brute force attack?
A brute force attack poses significant risks, particularly if your personal information or sensitive data is compromised. Once a cybercriminal successfully cracks a password or encryption key, they can gain unauthorized access to your accounts, devices, or networks, leading to various negative consequences, including major security breaches that can have long-lasting impacts on your digital and financial security.
- Risks to your personal information: Cybercriminals can steal your personal data, including login credentials, financial information, and private communications, potentially leading to identity theft or unauthorized transactions.
- Exploitation of your data: After gaining access, cybercriminals can use your information for fraudulent activities, phishing, or accessing other linked accounts, with far-reaching and sometimes irreversible effects.
- Potential impact on your daily life: A brute force attack can disrupt your life by locking you out of accounts, damaging your online reputation, or causing emotional distress, with recovery often requiring significant time and effort.
Types of brute force attacks
Brute force attacks can vary in their methods and complexity. Below are some of the most common types, each with a brief explanation of how they work and their potential impact.
- Simple brute force attacks
Simple brute force attacks involve manually or automatically trying all possible combinations of a password until the correct one is found. This type of attack is straightforward and relies on the strength of the password—short or commonly used passwords are especially vulnerable. While basic, this method can be surprisingly effective if users fail to implement strong password practices.
- Dictionary attacks
In a dictionary attack, cybercriminals use a list of commonly used passwords, often derived from actual dictionaries, to attempt to gain access to accounts. The attacker tests these passwords against a username until they find a match. Although dictionary attacks are not as comprehensive as other methods, they can be highly effective when targeting users who use weak or predictable passwords, such as “password123” or “qwerty.”
- Hybrid attacks
Hybrid attacks combine elements of dictionary attacks with simple brute force techniques. In this method, an attacker begins with a word list from a dictionary and then incorporates variations by adding numbers, symbols, or other characters. For example, a password like “Summer2024!” might be derived from the word “Summer” with the addition of a year and an exclamation mark. This approach increases the chances of cracking more complex passwords that still follow predictable patterns.
- Credential stuffing
Credential stuffing takes advantage of the common practice of reusing passwords across multiple sites. Cybercriminals use lists of previously stolen usernames and passwords, testing them on various platforms to gain unauthorized access. This method is particularly effective in large-scale attacks, where even a small success rate can yield significant rewards. Users who reuse passwords across different sites are especially at risk.
- Reverse brute force attacks
Unlike other brute force methods, reverse brute force attacks start with a known password and then attempt to find the correct username. This method is effective when a commonly used password, such as “password123” or “letmein,” is tested against a large number of potential usernames. Reverse brute force attacks exploit the tendency of some users to use simple, easily guessed passwords, potentially leading to widespread breaches if the password is popular.
Tools and techniques used in brute force attacks
Cybercriminals use various tools and techniques to carry out brute force attacks more efficiently. These tools automate the process, allowing attackers to test thousands or even millions of password combinations quickly, facilitating password cracking and making it easier for attackers to gain unauthorized access.
Common software tools cybercriminals use
- John the Ripper: An open-source password cracking tool that supports a wide range of encryption methods. It’s popular for its versatility and ability to crack passwords on various systems, including Unix, Windows, and more.
- Hydra: This tool is designed for parallelized login cracking. It supports numerous protocols like SSH, FTP, and HTTP, making it a versatile tool for targeting different systems.
- Aircrack-ng: A suite of tools specifically designed for assessing Wi-Fi network security. It includes features that allow attackers to crack wireless encryption protocols like WEP and WPA, giving them access to secured networks.
How these tools make attacks easier
- Speed: These tools can try thousands of password combinations per second, drastically reducing the time needed to crack a password.
- Efficiency: By supporting multiple protocols and encryption methods, these tools allow cybercriminals to target a wide variety of systems and services with minimal effort.
- Customization: Many of these tools allow attackers to create customized attack strategies, such as combining dictionary and brute force methods or focusing on specific types of encryption. This flexibility increases the likelihood of a successful attack.
How to protect yourself from brute force attacks
Protecting yourself from brute force attacks requires a combination of strong security practices and tools that help safeguard your accounts. Below are some essential strategies to help you stay secure:
- Create strong, unique passwords
Use passwords that are long, complex, and unique to each of your accounts. A strong password includes a mix of uppercase and lowercase letters, numbers, and special characters. Avoid using easily guessable information like common words, names, or dates. This makes it much harder for cybercriminals to crack your password using brute force methods.
- Use multi-factor authentication (MFA)
Multi-factor authentication (MFA) adds an additional layer of security by requiring not just a password but also a second form of verification, such as a code sent to your phone or an authentication app. MFA can also include biometrics, like fingerprint or facial recognition, which further strengthens security by adding something unique to the user that attackers cannot easily replicate.
- Use a password manager
Password managers help you create and store complex, unique passwords for all your accounts. They allow you to easily manage multiple strong passwords without the need to remember each one individually, reducing the temptation to reuse passwords across different sites.
- Keep your software and apps up to date
Regularly updating your software, including your operating system and any applications, ensures that you have the latest security patches installed.
What to do if you’re a victim of a brute force attack
If you suspect that you’ve been targeted by a brute force attack, it’s crucial to act quickly to minimize potential damage and secure your accounts. Below are the steps you should follow.
Signs that you’ve been attacked
Identifying a brute force attack can be challenging, but there are some warning signs that might indicate your account has been compromised:
- Unusual login attempts: You may notice alerts or notifications about login attempts from unknown locations or devices.
- Account lockouts: If your account suddenly gets locked due to too many failed login attempts, it could be a sign that someone is trying to brute-force your password.
- Unexplained activity: Watch for any unusual activity on your accounts, such as changes to your settings, unfamiliar transactions, or messages sent without your knowledge.
5 steps you should take immediately
If you suspect that your account has been compromised by a brute force attack, take the following actions immediately:
- Change your passwords: Update the passwords for any accounts that may have been affected. Ensure the new passwords are strong, unique, and not similar to your previous ones.
- Enable multi-factor authentication (MFA): If you haven’t already, enable MFA on all of your accounts to add an extra layer of security.
- Check your account settings: Review your account settings for any unauthorized changes, such as modifications to your recovery email or phone number.
- Log out of all sessions: Force a logout from all devices to ensure that any unauthorized access is terminated.
- Contact customer support: If your account has been severely compromised, contact the service provider’s customer support for assistance in securing your account and recovering any lost data.
Cybersecurity best practices against the brute force and other cyber attacks
After addressing the immediate threat, take these long-term steps to bolster your security and prevent future attacks:
- Monitor your accounts: Keep an eye on your account activity regularly to spot any unusual behavior early on.
- Use a password manager: A password manager can help you maintain strong, unique passwords for all your accounts, reducing the risk of using weak or repeated passwords.
- Educate yourself on cybersecurity: Stay informed about the latest security practices and threats to better protect yourself from future attacks by following our latest cybersecurity news and updates here: Malwarebytes Blog.
- Consider professional help: If you’re concerned about ongoing threats, consider consulting a cybersecurity professional to audit your online security and provide personalized recommendations.