How to prevent brute force attacks on your website

Key takeaways

• Brute force attacks are hacking attempts in which the malicious actor uses trial and error to correctly guess password combinations and gain access to user accounts.
• You can detect brute force attacks by configuring your network settings to notify you when it detects clear patterns, such as successive failed login attempts.
• You can prevent brute force attacks by implementing best practices, such as using complex passwords, enabling multi-factor authentication (MFA), and installing password managers.

A brute force attack occurs when hackers use guesswork to gain unauthorized access to user accounts.

Imagine you have a combination lock on your suitcase. A thief would try every possible combination on the dial to try and crack the lock. That would be an analog version of a brute force attack.

Hackers are becoming more vicious and prevalent thanks to the use of AI for malicious activities. But you don’t need to panic. Using tools like password managers and MFA, in combination with other techniques such as strong passwords that include special characters, can deter most brute force attack vectors.

Here, we’ll teach you all the ins and outs about brute force attacks and equip you with the knowledge you need to combat today’s online threats.

What are brute force attacks?

A brute force attack is a method where an attacker repeatedly tries different login credentials until they find the correct one. Instead of exploiting a technical vulnerability, this type of attack relies on volume and persistence, testing thousands or even millions of combinations until access is gained.

These attacks are usually automated. Attackers use scripts or bots to attempt common passwords, leaked credential lists, or variations based on known usernames. Because the process runs continuously and at high speed, even weak protections can be overwhelmed over time.

Brute force attacks often target login pages, admin panels, and remote access points such as file transfer protocol (FTP) or secure shell protocol (SSH). Any system that relies on username and password authentication is a potential target, especially if there are no limits on login attempts.

While brute force attacks are simple in concept, they can be effective against poorly secured systems. This is why strong passwords, access controls, and active monitoring play a key role in reducing the risk of unauthorized access.

How to detect brute force attacks?

Brute force attacks often follow clear patterns. Spotting them early gives you a better chance to stop the attack before real damage happens. You can detect brute force attempts by following these steps:

• Watch for unusual login activity
• Monitor server and application logs
• Track IP behavior and geolocation changes
• Set up alerts and thresholds
• Look for performance and availability issues

Watch for unusual login activity

Repeated failed login attempts are the most common signal. Pay attention to multiple failed logins from the same IP address, or a sudden spike in attempts across multiple accounts within a short period. Login attempts occurring at odd hours or in rapid succession can also indicate automation rather than legitimate users.

Monitor server and application logs

Your logs can reveal patterns that aren’t immediately apparent. Look for repeated requests to login pages, consistent error responses, or the same usernames being tried repeatedly. Reviewing authentication logs regularly helps you catch trends before they escalate.

Track IP behavior and geolocation changes

Brute force tools often rotate IP addresses to avoid detection. A single account being accessed from multiple locations in a short timeframe, or traffic coming from regions you do not normally serve, can be a red flag. IP reputation tools can help identify known malicious sources.

Set up alerts and thresholds

Automated alerts enable faster and more reliable detection. Set thresholds for unsuccessful login attempts, request rates, or authentication errors. When potential threat actors exceed the limits, alerts enable you to act immediately, rather than discovering the issue after the fact.

Look for performance and availability issues

In some cases, brute force attacks put noticeable strain on your server. Slower response times, increased CPU usage, or unexpected downtime may indicate a high volume of malicious login attempts running in the background.

Detecting brute force attacks is about pattern recognition and consistency. When you enact and review monitoring, suspicious behavior stands out long before it becomes a successful breach.

How does a brute force attack work?

Brute force attacks work through a step-by-step process, starting with the hacker identifying a vulnerability and ending with the attack propagating through different accounts or your system.

A brute force attack follows a predictable process, relying on repetition and automation rather than sophistication. Once set in motion, the attack continues until access is gained or the attacker is blocked.

Here’s the usual sequence of events:

1. The attacker identifies a login point: This could be a website login page, an admin dashboard, an email account, or a remote access service. Publicly accessible authentication forms are the most common targets.
2. The hacker prepares a list of credentials: Attackers use wordlists containing common passwords, leaked credentials from past breaches, or generated combinations based on patterns. Usernames can be derived from public profiles, email formats, or system defaults.
3. Automated tools launch repeated login attempts: Scripts or bots begin submitting login requests at high speed. Each attempt tests a different username and password combination, often without pauses between attempts.
4. The system responds to each attempt: If the server or system has no protections in place, it continues to accept login requests and return error messages. These responses help attackers confirm whether usernames exist or passwords are close to correct.
5. The hacker finds valid credentials
   • The attacker gains access once they crack passwords and user credentials. From there, they may escalate privileges, steal data, install malware, or move deeper into the system.
6. The attack continues or expands: In some cases, attackers reuse the same credentials across other accounts or services, especially if password reuse is common.

Brute force attacks succeed when systems allow unlimited attempts without detection or restriction. Understanding this process makes it easier to see where controls and safeguards can interrupt the attack before access is granted.

What are the types of brute force attacks?

Brute force attacks come in several forms, each using a slightly different approach to gain unauthorized access. Understanding these methods makes it easier to recognize attack patterns and apply the right protections.

• Simple brute force attacks: Attackers attempt every possible password combination until the correct one is found. This method is slow but can succeed against short or weak passwords.
• Dictionary attacks: Attackers use lists of commonly used passwords and words instead of guesswork. These lists often include predictable variations, such as adding numbers or swapping letters.
• Credential stuffing: Attackers reuse username and password combinations from previous data breaches and try them across multiple sites. This method works when users reuse credentials across services.
• Reverse brute force attacks: Hackers test common passwords against many usernames. This approach targets environments where default or reused passwords are widespread.
• Hybrid brute force attacks: This method blends dictionary attacks with minor modifications, such as adding upper and lowercase letters and symbols, to improve success rates.
• Password spraying: Attackers try a small number of common passwords across many accounts, spacing attempts out to avoid triggering lockouts or alerts.
• Rainbow table attacks: Attackers use precomputed tables of hashed passwords to quickly match stolen password hashes to their original values. While not always a direct login attack, this method becomes effective when password databases are exposed, and hashing practices are weak.

Each type of brute force attack exploits weak credentials, predictable behavior, or inadequate safeguards. Knowing how they differ helps you strengthen the right areas of your security setup.

How to prevent brute force attacks?

Preventing brute force attacks involves reducing opportunities for repeated login attempts and strengthening the process of granting access. These measures are most effective when used in combination, rather than applied in isolation.

Here’s what you need to do:

• Use strong passwords
• Use MFA
• Limit login attempts
• Use CAPTCHA
• Implement rate limiting and IP address blocking
• Consider passwordless authentication
• Set server configurations
• Observe user behavior
• Apply the principle of least privilege
• Train and educate your staff

Use strong passwords

Strong passwords make brute force attacks far less effective. Require long, unique passwords that combine letters, numbers, and symbols. Avoid using common or previously compromised passwords, and encourage the use of password managers to minimize password reuse.

Use MFA

MFA adds an extra layer of verification beyond passwords. Even if credentials are compromised, attackers cannot log in without the second factor, such as a one-time code or approval from an authentication app.

Limit login attempts

Restrict the number of failed login attempts allowed within a short period. Temporary lockouts or cooldown periods prevent attackers from making unlimited guesses and significantly slow automated tools.

Use CAPTCHA

CAPTCHA challenges help distinguish real users from automated bots. Adding them after a few failed login attempts can block automated brute force tools without disrupting normal users.

You can learn more about the intricacies and importance of the system from our guide on CAPTCHA and reCAPTCHA.

Implement rate limiting and IP address blocking

Rate limiting controls the number of requests an IP address can make within a specified time frame. When combined with temporary or permanent IP blocking, it helps prevent high-volume attack traffic from reaching your authentication system.

Our tutorial on how to block IP addresses can help get you started!

Consider passwordless authentication

Passwordless methods, such as magic links, biometric verification, or hardware-based authentication, eliminate the need for passwords altogether. This eliminates one of the main targets of brute force attacks.

Set server configurations

Harden server settings to reduce exposure. This includes securing admin endpoints, disabling unnecessary services, enforcing secure protocols, and applying firewall rules to protect login-related paths.

Observe user behavior

Monitoring login patterns helps identify suspicious activity early. Unusual login times, location changes, or rapid authentication failures can indicate brute force attempts and trigger protective actions.

Apply the principle of least privilege

Limit user access to only what is necessary for their role. Even if an account is compromised, restricted permissions reduce the potential impact of unauthorized access.

Train and educate your staff

Human behavior plays a major role in account security. Educate staff on best practices for strong passwords, phishing awareness, and safe authentication habits to reduce the likelihood of credentials being compromised in the first place.

What are the negative impacts of brute force attacks?

Brute force attacks can affect both security and business operations, even when they do not immediately succeed. You’d want to do your best to avoid the following:

• Unauthorized access and data exposure: Attackers who gain access can view, steal, or modify sensitive data, putting user information and internal systems at risk.
• Account takeovers: Compromised accounts may be used for fraud, impersonation, or further attacks, creating issues for both users and support teams.
• Service performance issues: Large volumes of login attempts can strain servers, slow down legitimate traffic, or cause temporary outages.
• Financial losses: Costs may include fraud, incident response, system recovery, legal fees, and lost revenue during downtime.
• Reputational damage: Security incidents reduce user trust and can harm a brand’s credibility long after the attack is resolved.
• Compliance and legal risks: Weak protections that lead to breaches can result in regulatory penalties or legal consequences.
• Expanded security risks: Once access is gained, attackers often attempt privilege escalation or lateral movement, increasing overall exposure.

Even unsuccessful brute force attacks can have lasting consequences if detection and prevention measures are not in place.

Frequently asked questions

Keep your website and customers secure with Network Solutions

Brute force attacks can compromise your website, leaving your customers vulnerable to security breaches. Ignoring them can damage your reputation, result in financial losses, and even put your business at risk.

But with proper defenses, you can sidestep the attacks altogether. Leveraging account authentication, implementing strong passwords, and monitoring server status are just some of the ways you can protect yourself against a brute force attack.

With the help of our dedicated security system, SiteLock, you can protect yourself against most malicious attacks—including brute force. Additionally, our SSL certificates can encrypt your sensitive information and provide your customers with peace of mind.