OpenBullet is a powerful and popular tool threat actors use to perform large-scale automated attacks. Its versatility, ease of use, and cost-effectiveness make it a force to be reckoned with.

In August 2022, the FBI warned cybersecurity professionals worldwide that credential stuffing attacks are becoming more sophisticated. Today, bad actors leverage the power of proxies and configurations to automate attacks.

Although the FBI’s warning did not mention OpenBullet by name, it described “custom configuration(s) for credential stuffing activities,” which can also refer to the configs that OpenBullet users implement to execute automated cyber attacks quickly.

Companies that host large numbers of customer accounts are at great risk. The low barrier to entry for software like OpenBullet makes it ridiculously easy for cybercriminals to launch devastating credential stuffing attacks.

So, what exactly is OpenBullet, and how did it become so popular among cybercriminals? Let’s dive into the details of OpenBullet’s meteoric rise and assess how bad actors use the software today.

What is OpenBullet?

We would define OpenBullet as an automation tool designed to make the process of launching sophisticated attacks easier and faster. Although its creator initially developed it for legitimate use, its potential for malicious activities quickly became apparent.

OpenBullet is open-source software that allows users to launch a variety of attacks, including:

  • Brute force
  • SQL injection
  • Credential stuffing
  • Account takeover
  • Account checking
  • CAPTCHA cracking

OpenBullet also provides users with access to a large repository of tools and data that can be used for malicious activities. From an attacker’s perspective, OpenBullet automated attacks offer two major advantages: speed and scalability. With OpenBullet, a bad actor can launch an attack with minimal effort and in a much shorter time span.

Currently, the most popular attacks that are being conducted with OpenBullet are credential stuffing attacks. In these attacks, malicious actors use stolen credentials to gain access to large numbers of accounts. With the help of the tool, they can launch automated and distributed attacks using a single computer.

How OpenBullet Works

Under the hood of OpenBullet are popular web automation testing tools, Google Puppeteer and Selenium. Open Bullet uses a proxy manager to send requests to websites or other internet services. These requests are sent using different IP addresses, making it difficult for the target service to detect and block malicious activities.

The open source software also includes an intuitive Graphical User Interface (GUI) that makes it easy for users to build and set up their attacks. OpenBullet supports a wide range of web-based attack methods, including SQLi (structured query language injection), XSS (cross-site scripting), brute force, and credential stuffing.

Additionally, OpenBullet comes with several pre-built templates that users can use as starting points to create their own attacks. These are called “configs,” and they allow users to quickly configure their attacks.

The History of OpenBullet

OpenBullet became problematic soon after its launch to the public in May 2019. It was designed to be a user-friendly automation tool for red teamers and penetration testers. However, the sheer power of OpenBullet quickly attracted malicious actors.

By December 2019, OpenBullet had already gained a reputation as a powerful tool for malicious activities. The community continued to grow and take on a more sinister tone. Cybercriminals started using the tool to launch sophisticated attacks, and it was only a matter of time before OpenBullet became a staple of the criminal underground.

Enter the COVID-19 pandemic. With the world in lockdown, attackers had more targets than ever before. Video conferencing apps saw a massive surge in usage and became prime targets for credential stuffing attacks.

As a result, OpenBullet gained even more notoriety as the tool of choice for cybercriminals. The financial impact of the pandemic drove more people to engage in malicious activities, which added fuel to the fire.

And what about today? OpenBullet is even more powerful, with its new version OpenBullet 2. The community is strong and growing, with attackers constantly looking for new ways to use and improve the software. Despite some law enforcement efforts to address the issue, it remains a threat to online businesses that should not be taken lightly.

Configs Are the Key to Successful OpenBullet Attacks

As we mentioned, configs are pre-built scripts that contain all the settings and parameters necessary for launching an attack. With OpenBullet, there is no shortage of configs available.

The dark web is full of configs designed for different types of attacks. Cybercriminals can purchase or rent these configs, making them a valuable resource in the world of automated attacks.

Configs are important because they save attackers time and money. They allow users to launch sophisticated attacks without having to build their own scripts from scratch.

However, configs are not one-size-fits-all solutions. Attackers must customize their configs to match their targets, which is why they often purchase or rent the latest and most sophisticated configs available. Some configs are tailored to specific websites, while others have more broad use cases.

How Attackers Install and Use Configs

Once an attacker has the config they need, they can install it at lightning speed. To install a config, attackers simply drag and drop the file into OpenBullet.

The software reads the config, parses it into its components, and creates a GUI for the user to set up their attack. Yup, it’s really that easy. Anyone can launch an attack in a matter of minutes, and the rate at which they can launch attacks is only limited by their computing power.

As for the actual attack, once the user has configured their settings they can start running their scripts. OpenBullet automates the entire process and allows attackers to quickly launch attacks against their targets.

Another factor to keep in mind is that attackers share configs with each other all the time. They often do this in exchange for money or other favors. The demand for configs creates a strong network of attackers who are all working together to launch successful attacks.

Types of OpenBullet Attacks

Now that we’ve covered the basics of OpenBullet, let’s take a look at some of the most common use cases for this software.

Brute-Force Attacks

Brute-force attacks are one of the most common uses for OpenBullet. These attacks involve trying every possible combination of characters to guess an account’s username and password.

How It Works: OpenBullet will send requests to the target website with different username and password combinations until it finds one that works.

SQL Injection

SQL injection attacks are also popular with OpenBullet users. These attacks involve inserting malicious code into a website’s database in order to gain access to it.

How It Works: OpenBullet will send requests containing malicious code to the target website. If successful, this code can grant access to the database and allow the attacker to steal sensitive information such as credit card numbers and user passwords.

Credential Stuffing

Credential stuffing is a popular cyberattack method that involves using stolen credentials to gain unauthorized access to online accounts. Attackers can purchase lists of usernames and passwords from the dark web, then use OpenBullet to automate the process of checking them against a target website or service.

How It Works: The attacker first creates a list of usernames and passwords. They then use OpenBullet to “stuff” these credentials into target websites or services. This process involves sending large amounts of traffic to the target, which can overwhelm their system and potentially lead to a breach.

Account Takeover

Account takeover (ATO) is another popular use case for OpenBullet. An ATO attack involves hijacking a user’s account on a website or service and using it to commit fraud or other malicious activities.

How It Works: Attackers typically use credential stuffing to gain access to the target’s account, then employ OpenBullet to automate processes related to the takeover. This could include sending emails or transferring funds, for example.

Account Checking

Account checking is the process of using OpenBullet to determine which accounts on a service or website are still active. This can be used to facilitate account takeover attacks, as well as identify potential targets for further exploitation.

How It Works: The attacker uses OpenBullet to send requests to the target’s website or service in order to check which accounts are still active. This can be done manually or automatically, depending on the attacker’s preferences.

CAPTCHA Cracking

CAPTCHA cracking is the process of using OpenBullet to bypass a website’s CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) system. This allows attackers to gain access to restricted areas of a website, such as accounts or payment forms

How It Works: The attacker first creates a script with OpenBullet that can submit CAPTCHA responses. They then use the script to automate the process of bypassing a website’s CAPTCHA system. This can be done manually or automatically, depending on the attacker’s preferences.

How OpenBullet Compares to Similar Tools

OpenBullet is not the only tool available for performing cyberattacks. Other popular tools include Burp Suite, Metasploit, Social Engineering Toolkit (SET), and Nessus. Here’s how each tool stacks up against OpenBullet.

Burp Suite

Burp Suite is a web application security testing tool. It’s designed to help developers identify and fix potential vulnerabilities in their websites or applications. OpenBullet is better suited for offensive security tasks, such as brute-force attacks or credential stuffing.


Metasploit is an open source exploitation framework that can be used to execute various types of attacks on vulnerable systems. While Metasploit offers more flexibility than OpenBullet, it may not always be the best option for beginners who are just getting started with cyberattacks.

Social Engineering Toolkit (SET)

SET is a social engineering toolkit designed to help attackers manipulate people into giving up sensitive information or access to restricted systems. While SET can be used for some similar tasks as OpenBullet, it’s primarily focused on psychological manipulation rather than technical exploitation.


Nessus is a vulnerability assessment tool that scans networks and systems for potential security flaws. While Nessus can be used in conjunction with OpenBullet to identify targets, it’s not typically used as an offensive security tool like OpenBullet is.

Overall, OpenBullet is a powerful open-source tool for performing various types of cyberattacks. Let’s take a look at what really sets it apart.

Advantages of Using OpenBullet

Here’s why many cybercriminals use OpenBullet to perform their attacks:

  • It’s Easy to Use: OpenBullet is relatively easy to use, even for those with little or no experience in cyberattacks. Attackers can easily create, edit, and use configs. It only takes a few minutes to get up and running. OpenBullet’s ease of use means that there is a low barrier to entry for attackers. They don’t have to be experienced coders to use it.
  • It’s Open-Source: OpenBullet is an open-source tool, which makes it easy to tailor to your needs or add new features. Many users have contributed to the development of OpenBullet, meaning there is a wide variety of scripts and configs available. A quick search on the dark web will turn up configs that attackers can use to target specific websites or services.
  • It Has Fast Results: OpenBullet is designed to perform attacks quickly and efficiently. It can be used to brute-force accounts or bypass CAPTCHAs in a matter of minutes. Its agility allows attackers to quickly gather the information they need before the victim detects and stops the attack.
  • It’s Highly Versatile: OpenBullet offers a lot of flexibility when it comes to selecting attack vectors and configuring scripts. With OpenBullet, malicious actors can bypass common security measures, such as two-factor authentication or IP blocking. This makes OpenBullet a powerful tool for attackers who want to gain access to restricted systems or information.
  • It’s Cost-Effective: OpenBullet is free, so there is no need to purchase expensive tools or licenses. This makes OpenBullet a great option for attackers who are working on a budget. It also means that bad actors can quickly gain access to their desired information without paying anything upfront.
  • It Has a Thriving Online Support Community: There is a large online community of OpenBullet users who are willing to help each other out. Attackers can find configs and scripts on the dark web or in online forums, as well as ask questions and receive advice from more experienced attackers. This makes it easy for newcomers to get up to speed with OpenBullet quickly.

OpenBullet offers many benefits to attackers of all skill levels, and it makes perfect sense why it has become so popular with cybercriminals. With a wide range of features, its versatility and flexibility make it an ideal tool for malicious actors looking to gain access to sensitive data or restricted resources.

Advantages of openbullet

What Type of Data Can OpenBullet Steal?

Attackers can use OpenBullet to collect a variety of data, including:

  • Usernames
  • Passwords
  • Email addresses
  • Credit card numbers
  • Health records
  • Private messages
  • Images from social media accounts

Here’s how OpenBullet exploits different types of data:

  • Usernames: Attackers use OpenBullet to brute-force login credentials for different websites or services. This allows them to access accounts without the victim’s permission.
  • Passwords: OpenBullet can perform dictionary attacks, which involve trying out commonly used words and phrases as passwords. Attackers can quickly gain access to accounts that are protected with weak passwords.
  • Email Addresses: In addition to usernames and passwords, attackers can harvest email addresses using OpenBullet. They can use these email addresses to send malicious links or phishing emails. In a phishing attack, bad actors send emails that appear to be from a legitimate company or website, prompting the victim to enter their username and password. Common phishing attacks include fake emails from banks or online stores.
  • Credit Card Numbers: Attackers often use OpenBullet to obtain credit card numbers in order to make unauthorized purchases. First, bad actors will also use OpenBullet to collect information about the cardholder, and then use it to finalize the transaction.
  • Health Records: OpenBullet can be used to access confidential medical records and other sensitive data related to a person’s health. Attackers that target healthcare organizations can use OpenBullet to steal information such as Social Security numbers, insurance details, and more.
  • Private Messages: Private messages are not safe from OpenBullet either. Attackers can use OpenBullet to target specific messaging services to access conversations and data. For example, they can use OpenBullet to access sensitive information on Skype, Telegram, WhatsApp, and other messaging services. With over 2 billion active users, WhatsApp is a prime target for attackers.
  • Images from Social Media Accounts: Attackers can also use OpenBullet to access images from social media accounts. With OpenBullet, malicious actors can target specific accounts and obtain pictures without the victim’s knowledge. The automation power of OpenBullet makes this process quick and efficient. It can scrape data from thousands of accounts in a short amount of time.

By compiling data from multiple sources, attackers can gain a better understanding of their target, enabling them to launch more sophisticated attacks. Whether it’s used to steal data, gain access to restricted resources, or launch social engineering attacks, OpenBullet is a powerhouse in the eyes of malicious actors.

What Happens After a Successful OpenBullet Attack?

To understand the sheer power of OpenBullet, it’s important to consider the attackers’ endgame. After successfully breaching the target, attackers will usually monetize the data in one way or another. Financial gain is often the ultimate goal, and there are several ways to achieve it.

Here are some of the ways OpenBullet attacks benefit attackers and destroy victims:

Selling Stolen or Compromised Data

Attackers can use the data collected with OpenBullet and sell it on the dark web. Criminal organizations or other malicious actors are eager to purchase credit card numbers, login credentials, and other confidential information.

Identity Theft

With OpenBullet, attackers can easily steal enough personal data to commit identity theft. This crime involves using someone else’s confidential information to gain access to their accounts, take out loans in their name, and more.

Phishing Campaigns

In addition to stealing data, attackers can use OpenBullet to launch phishing campaigns. With the information they gather, they can craft personalized emails that appear to come from a legitimate source. These emails often contain malicious links or attachments that are designed to get the victim’s confidential information.

Creating Fraudulent or Fake Accounts

Attackers can use the stolen data to create fraudulent accounts in the victim’s name. This can include creating bank accounts, credit card accounts, and more. With this information, the attacker can quickly purchase items without the victim’s knowledge or leverage the accounts to conduct other forms of fraud.

Launching Social Engineering Attacks

With the information gathered from OpenBullet, attackers can craft social engineering attacks that are specifically tailored to the victim. These attacks often involve convincing the victim to provide their login credentials or other sensitive information.

Blackmail and Extortion

Attackers can use the data they gather from OpenBullet to blackmail or extort the victim. They may threaten to release compromising information or pictures if the victim does not comply with their demands.

These are just a few of the ways attackers can benefit from OpenBullet. It’s important to understand the risks posed by this sophisticated tool and take steps to protect yourself.

How to Stop an OpenBullet Attack

Want to know the best way to stop an OpenBullet attack? By being proactive and stopping it before it starts.

Once a bad actor successfully launches an OpenBullet attack against your organization, it’s often too late. The damage is already done and reversing the attack can be difficult, time-consuming, and expensive.

Here are several preventative measures you can take to keep your data safe from an OpenBullet cyberattack:

Implement Multi-Factor Authentication (MFA) or Two-Factor Authentication (2FA)

MFA and 2FA add an extra layer of authentication, making it harder for attackers to gain access to your accounts. The difference is that MFA requires more than two authentication factors while 2FA only requires two.

Examples of Authentication Factors:

  • Knowledge, such as a password or PIN
  • A physical item, such as a smartphone or token
  • A part of you, such as a biometric scan, such as a fingerprint or voiceprint

So, which is better: MFA or 2FA? It depends on the level of security you need. MFA is typically more secure than 2FA, but it also requires more effort to set up and maintain. Consider your budget, resources, and security goals when deciding which authentication method to use.

Use a Strong Password and Change it Regularly

A strong password is one of the best ways to protect your accounts from attacks. It should contain a mixture of uppercase and lowercase letters, numbers, and special characters.

The optimal password length for maximum security is 12 characters, so make sure your password is at least that long. (We know that’s a lot of characters to remember, but you can always use a password drive to store your credentials securely.)

We also recommend creating a company-wide rule that requires employees to change their passwords every 30 days.

Be Wary of Unknown Links and Attachments

Never click on a link or open an attachment from an unknown source. These links and files can contain malicious code that will give attackers access to your data.

If you receive an email from a source you don’t know, check the domain name of the sender to see if it looks legitimate. If there is any doubt, delete the email and report it to your IT department.

Train Your Employees

Employees are often the first line of defense against cyberattacks. Educating them on cybersecurity best practices, such as recognizing phishing emails or spotting suspicious activity, is essential for keeping your data secure. Make sure to regularly train and update your employees on the latest security threats.

You should also review your security policies and procedures with your employees and remind them of their responsibilities for protecting company data.

Monitor Your Network Activity

System logs and network traffic can reveal anomalies that may indicate a breach. Regularly monitor your network for any suspicious activity and review logs for any abnormal behavior.

Suspicious Activity to Look For

  • Traffic from known malicious IP addresses
  • Unusual spikes in network traffic
  • Data being downloaded or uploaded to a suspicious domain

If you notice any of these signs, investigate further and contact your IT department for help.

Make Sure All Software is Up-to-Date

By regularly updating your software and applications, you can ensure that the latest security patches are installed and reduce the chance of a successful attack. Keep all of your hardware and software up-to-date with the latest security patches. This will reduce the chance of a successful attack.

Use a Security Scanner and Firewall

A security scanner is an application that scans your computer for viruses, malware, and other malicious software. It can also detect suspicious activity and alert you to potential threats.

On the other hand, a firewall is a security system that monitors incoming and outgoing network traffic and blocks any malicious traffic. This helps to protect your data from attackers and hackers.

These tools are essential for keeping your data secure. Use both to ensure maximum protection.

Utilize User Behavior Analytics (UBA)

User behavior analytics (UBA) is a security solution that monitors user activity on your network. It tracks how users interact with the system and can detect suspicious behavior.

UBA can help detect insider threats, malicious activity, and user errors that may lead to a data breach. Utilize this security tool to stay ahead of any potential threats.

IMPORTANT: Back Up Your Data Regularly

Data backups are essential for any security strategy. They help you recover lost or corrupted data in the event of a disaster or attack. In the worst-case scenario, you can restore your data from the backup with minimal disruption to your operations.

Make sure you regularly back up critical files and store them in a secure, offsite location. This way you can keep your data safe even in the event of an attack. We recommend setting up an automated backup system so you don’t have to worry about manual backups. You should back up your data at least once a week for the best results.

Steps to Take in the Event of a Successful OpenBullet Attack

If you believe your organization has been the victim of an OpenBullet attack, this is what you should do:

  • Alert Your IT Department Immediately: They’ll be able to investigate the issue and take action to protect your data.
  • Change Passwords and Lock Down Systems: Change all passwords on affected systems to ensure that attackers don’t have access to any sensitive data. You should also limit user access and lock down any systems that were compromised.
  • Check for OpenBullet Malware: Run a scan to check for any OpenBullet malware on your systems. If you find any, remove it and update your security measures to prevent future attacks.
  • Implement a Bot Detection and Mitigation Solution: Robust bot detection and mitigation solutions can help you identify and deal with attacks launched using OpenBullet. They provide an additional layer of security to protect your data from attackers.

So, what makes bot mitigation software so beneficial? Let’s take a closer look at why every organization should consider investing in an anti-bot solution.

What is Bot Mitigation?

Bot mitigation enables you to detect and block malicious bots from accessing your systems. Bot mitigation software uses advanced algorithms to identify suspicious bot activity and blocks it before any damage can be done. It also provides insights into the tactics used by attackers so you can better protect your systems in the future.

Investing in a bot mitigation and detection solution is an effective way to protect your business from OpenBullet attacks and other malicious bots. It can help you identify and block threats before they can cause any damage. Implementing a bot mitigation solution is an important step in protecting your organization from cyberattacks.

Kasada Stops Bad Bots For Good

Kasada is the only bot mitigation solution on the market that adapts as quickly as attackers. Kasada is proactive, as the platform truly detects and prevents automated threats in real-time. Many of our competitors focus on reactive measures like blocking IP addresses, which only manage the attack after it has already happened.

Rule-based, static defenses are no match for advanced attackers and bots. Sophisticated bots can easily adapt to retooling and reverse engineering techniques. CAPTCHAs and other common defenses are futile.

That’s exactly why you should choose us. At Kasada, we provide the easiest, most effective way to stop bad bots from accessing your network.

Automated threats evolve rapidly. Since OpenBullet configs can be created so quickly and easily, it’s important to ensure your organization is well-protected against credential stuffing and account takeover. Our threat intelligence and research teams work to be one step ahead of the latest security threats.

Our team at Kasada is passionate about keeping data safe. Security doesn’t sleep, so we offer 24/7/365 support services to resolve issues that arise at any time.

Ready to See Kasada in Action?

Request your personalized demo to see how the Kasada Bot Defense Platform can protect your organization today.

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