Introduction: Brute Force Attack: What It Is and How to Protect Against It 

Brute-force attacks are a type of cyber assault where attackers systematically guess passwords or encryption keys until they find the correct one. It’s a trial-and-error method, often powered by automated tools, that can quickly run through millions of combinations to break into accounts, systems, or networks.

These attacks exploit weak passwords, reused credentials, and poor security configurations. Brute-force attacks are mechanical and relentless. And thanks to cloud computing and readily available tools, they’ve become faster, cheaper, and more scalable than ever before.

In today’s digital world, brute-forcing doesn’t just target individuals — businesses of all sizes, especially those with exposed login portals or unsecured APIs, are at serious risk.

What Is a Brute Force Attack?

A brute force attack is a trial-and-error method used to gain unauthorized access to systems, accounts, or encrypted data. Attackers systematically try every possible combination of usernames and passwords until they find the correct one.

There are several variations:

• Simple brute force: Guessing passwords without any context or external information.

• Dictionary attacks: Using a precompiled list of likely passwords (like “123456” or “qwerty”).

• Credential stuffing: Using stolen username-password pairs from previous breaches to attempt logins on other services.

Although brute force attacks can be time-consuming, they’re easily automated and often highly effective due to poor password hygiene.

Credential-Stuffing Attacks Are Surging

One of the most common forms of brute-forcing today is credential stuffing — where attackers use previously leaked username/password pairs to attempt logins on other websites. These credentials are usually harvested from large-scale data breaches and sold on the dark web.

Here’s what makes these attacks so dangerous:

• They exploit human behavior: Many people reuse the same password across multiple sites.

• They’re automated and fast: Tools like Hydra, Burp Suite, or SentryMBA can try thousands of combinations per minute.

• They often go undetected: The login attempts can look like normal user traffic.

Recent trends show credential-stuffing attempts increasing during events like tax season, shopping holidays, or after a high-profile data breach — times when users are most distracted.

Real-World Attack Example: 2012 LinkedIn Data Breach

What Happened: In 2012, LinkedIn suffered a massive data breach in which hackers stole over 6.5 million hashed passwords. Initially, the hashes were unsalted SHA-1 hashes, which are relatively easy to crack.

How the Brute-Force Attack Worked:

1. The attacker obtained the leaked password hashes.

2. Using brute-force techniques and dictionary attacks, they used software like Hashcat or John the Ripper to try billions of password combinations against the hash values.

3. Because LinkedIn didn’t salt their hashes, many passwords were cracked very quickly, especially weak ones like “123456” or “linkedin”.

Impact:

• Many users reused their passwords on other sites, leading to credential stuffing attacks.

• LinkedIn was heavily criticized for poor password storage practices.

• Eventually, over 117 million LinkedIn users’ emails and passwords were found being sold on the dark web in 2016.

Why These Attacks Still Work So Well

There are a few key reasons brute force and credential stuffing attacks remain effective:

1. Password Reuse: Many users recycle passwords across services, making one breach a gateway to others.

2. Weak Passwords: Despite warnings, simple passwords like “password123” are still common.

3. Lack of Rate Limiting: Some websites don’t limit the number of login attempts, enabling automated brute force tools.

4. No Multi-Factor Authentication (MFA): Without MFA, a stolen password is often all an attacker needs.

How to Stay Safe: Practical Tips for Users and Organizations

For Individuals:

• Use Strong, Unique Passwords: Every account should have a different, complex password.

• Enable MFA Everywhere: Multi-factor authentication adds an extra layer of protection.

• Use a Password Manager: These tools generate and store strong passwords so you don’t have to remember them all.

• Monitor Your Accounts: Watch for suspicious login activity or password reset attempts.

For Organizations:

• Implement Rate Limiting: Restrict the number of login attempts to slow down brute force efforts.

• Enforce Strong Password Policies: Require complex and unique passwords.

• Detect Anomalies: Use behavior-based systems to identify unusual login patterns.

• Require MFA for All Users: Especially for administrative or high-privilege accounts.

• Check for Credential Reuse: Integrate tools that scan known data breach lists against your user base.

How Logstail Academy Can Help You Stay Safe

Understanding how brute-force attacks work is the first step toward stopping them. Logstail Academy offers dedicated training modules on threat detection, SIEM log analysis, and brute-force mitigation strategies.

The “Brute Force Attacks: How to Identify and Mitigate with SIEM” comprehensive course on Logstail Academy , provides an in-depth exploration of brute force attacks, including real-world case studies, detection methodologies, and effective mitigation strategies using Security Information and Event Management (SIEM) systems. Designed for IT professionals and business leaders alike, this training equips you with the tools and knowledge necessary to proactively identify automated attacks and implement countermeasures before significant damage occurs.

In addition to the detailed lessons, the course includes quizzes to reinforce your learning, allowing you to test your understanding and ensure you’re prepared to handle real-world security challenges.

Enhanced Brute-Force Detection with Logstail SOAR

With Logstail’s advanced security monitoring capabilities, you can easily protect your systems from unauthorized access attempts, brute force attacks, and other security threats. The platform offers a built-in solution designed to detect brute-force enumeration attempts specifically targeting Windows OpenSSH servers—without the need for custom rule creation.

One of the standout features is the “Detect Brute Force Enumeration on Windows OpenSSH Server” rule, which is pre-configured and available in the Logstail SOAR library. This feature enables you to instantly monitor and respond to brute-force login attempts, providing an extra layer of defense for your environment.

Here’s how it works:

• Seamless Detection: Logstail’s SOAR platform automatically detects brute-force attacks by flagging suspicious enumeration attempts on Windows OpenSSH servers. The built-in detection rule helps you stay on top of potential threats without having to manually configure or fine-tune complex detection criteria.

• Comprehensive Alerts: When a brute-force attack is detected, Logstail generates an alert that provides full visibility into the event. The alert includes crucial information such as the source IP address, usernames being targeted, and the exact timestamp of the attempted login, enabling you to take swift action.

• Instant Alert Management: The platform offers an intuitive Alerts Dashboard, where you can easily view, manage, and investigate security alerts. You can drill down into the details of each alert to understand the scope of the attempted attack and make informed decisions for response.

• Proactive Security: By leveraging Logstail’s built-in security rules, your system is actively safeguarded against brute-force attacks, allowing you to focus on other priorities while ensuring that your servers are continuously monitored for emerging threats.

With Logstail SOAR, securing your Windows OpenSSH environment from brute-force enumeration attacks is not only possible, it’s streamlined and automated, giving you peace of mind.

What Happens When the Alert is Triggered?

When the Detect Brute Force Enumeration on Windows OpenSSH Server rule is triggered, Logstail SOAR will raise an alert in your dashboard with detailed context:

• Alert Name: Brute Force Enumeration on Windows OpenSSH

• Agent Name: The machine or server where the event was detected

• Severity: (Typically marked as High for potential brute-force attacks)

• Timestamp: The exact time the suspicious event occurred

• View Log: A direct link to the raw event log, giving you further details on the detected brute-force attempt.

This helps you respond promptly to potential security threats, automating a significant part of the detection and alerting process

By automating alerts for SSH Brute-Force attacks, organizations can drastically improve their security posture. These alerts enable swift responses to potential threats, helping to protect the integrity of the network environment. Not only does this approach increase security, but it also aligns with best practices in network management and threat detection.

Final Thoughts

While brute-force attacks may appear simple, they are remarkably effective, persistent, and continuously evolving. Given the right tools and time, attackers can exploit any vulnerability in inadequately secured systems.

Don’t leave your defenses vulnerable. Strengthen your security, continuously monitor your networks, and invest in regular cybersecurity training. Whether safeguarding personal accounts or enterprise infrastructures, even a single weak password can be the gateway for an attack.

Stay vigilant. Prioritize long-term, robust security, and never underestimate the potential of automated attacks in the wrong hands.

Contact Our Experts  or Sign Up for Free