What Is Password Spraying and How Do You Prevent It?

Password spraying is an account takeover (ATO) cyberattack where attackers use a single common password or a handful of common passwords to try to access many accounts. This method spreads out login attempts across numerous accounts, making it harder to detect and block.

By using password spraying, attackers can effectively take over user accounts, leading to unauthorized access and potential exploitation of sensitive information.

These attacks are increasingly common and can lead to data breaches, financial loss, and damage to your organization's reputation. Understanding password spraying and how to defend against it is key to maintaining security.

Password spraying attacks follow a systematic approach:

• Reconnaissance and target selection: Attackers identify potential targets by gathering information about an organization's user accounts.
• Credential harvesting and username enumeration: They collect usernames through phishing, data breaches, and/or public sources.
• Password guessing: Using common or leaked passwords, attackers attempt to log in to multiple accounts. They do this by trying a few passwords per account to avoid detection.
• Identifying successful logins: Successful logins are flagged, giving attackers unauthorized access to the system.

On the surface, there are many similarities between password spraying, brute force attacks, and credential stuffing. But as you dig deeper, you’ll find that there are key differences between them.

Before we dive into the details of each type of attack, remember this: all three are typically automated attack vectors that aim to take advantage of bad passwords and poor password hygiene.

Password Spraying

Password spraying is a subset of brute force attacks. Instead of relentlessly trying every possible password combination for a single account (like a traditional brute force attack), password spraying focuses on a limited set of common passwords across a large number of accounts.

This distributed approach makes it trickier to detect because login attempts are spread out. This helps avoid triggers like account lockout policies.

In many ways, password spraying preys on the predictable nature of humans. Many people reuse the same weak passwords across different accounts. Hackers exploit this by using well-known leaked password lists or simply trying common password combinations like "password123" or variations with birthdays or names.

Traditional Brute Force Attack

As the name implies, a traditional brute force attack is a more straightforward approach. It involves rapidly trying a large number of different passwords on a single account. This can be anything from systematically iterating through all possible combinations of characters to using leaked password dictionaries.

Brute force attacks are a dual-edged sword for attackers. While their relentlessness might seem advantageous, it also makes them incredibly easy to detect. The constant barrage of login attempts throws up red flags for security systems, which can trigger account lockouts after a set number of failed tries. This locks the attacker out, preventing them from ever gaining access to the targeted account.

Credential Stuffing

Credential stuffing takes a different route from password spraying or brute force attacks. Instead of guessing passwords, it leverages stolen credentials. Hackers use lists of usernames and password combinations obtained from data breaches to try logging into accounts across various platforms.

Similar to password spraying, credential stuffing distributes login attempts across multiple accounts to make detection difficult. However, unlike password spraying which relies on common guesses, credential stuffing uses actual compromised login information, potentially increasing its success rate. The primary difference lies in the attacker's knowledge. Password spraying attacks try various passwords without knowing if they're correct. This is in contrast with credential stuffing attempts that exploit existing compromised credentials.

Password spraying attacks can have severe consequences and pose significant risks to organizations. Understanding these impacts helps underscore the importance of advanced security measures.

Data Security Risks

Successful password spraying attacks can lead to unauthorized access to sensitive data. Once attackers gain access to an account, they can steal confidential information, such as personal data, financial records, or intellectual property. This breach of data security can result in severe financial losses, legal liabilities, and long-term damage to an organization's trust and credibility.

Reputation Damage

Organizations that fall victim to password spraying attacks often suffer substantial reputational harm. News of a data breach can erode customer trust and confidence, leading to a loss of business and market share. Customers and clients may perceive the organization as negligent in protecting their information, which can have lasting effects on brand loyalty and public perception.

Regulatory Compliance

In many industries, regulatory bodies require organizations to implement stringent security measures to protect sensitive data.

Failure to prevent password spraying attacks can result in non-compliance with regulations such as the General Data Protection Regulation (GDPR) or the Health Insurance Portability and Accountability Act (HIPAA). Non-compliance can lead to hefty fines, legal actions, and increased scrutiny from regulatory authorities.

Real-World Examples and Costs

1. Dunkin’ Donuts (2018): In a high-profile case, Dunkin’ Donuts faced a credential stuffing attack, closely related to password spraying. Attackers gained access to customer accounts, leading to unauthorized purchases and loss of loyalty points. The incident damaged the brand’s reputation and led to significant remediation costs.
2. Citrix (2019): Citrix, a major software company, suffered a breach where attackers used password spraying techniques to gain access to its internal network. Sensitive data of over 76,000 individuals was compromised, resulting in regulatory scrutiny and substantial financial costs related to incident response and legal fees.

Cost Implications

The financial impact of password spraying attacks can be staggering. Organizations may face direct costs such as incident response, forensic investigations, and legal fees. Indirect costs, including reputational damage, loss of customers, and increased insurance premiums, can also add up.

For instance, IBM’s 2020 Cost of a Data Breach Report estimated that the average total cost of a data breach is $3.86 million, with a significant portion attributed to lost business and reputational harm. Since password spraying can be the first step in an account takeover, which can lead to such breaches, the importance of preventing these attacks cannot be overstated.

Identifying password spraying attacks early can help mitigate their impact and protect your organization’s data. Here are some signs and indicators to watch for:

• High number of failed login attempts for multiple user accounts: Multiple failed login attempts across different accounts can indicate an ongoing password spraying attack. This pattern suggests attackers are systematically testing passwords on various accounts to find a match.
• Unusual login patterns or access from unfamiliar locations: Monitoring login activity for irregular patterns or access from unexpected geographic locations can help detect potential attacks. Such anomalies often signal that an attacker is attempting to breach accounts from remote locations.
• Login attempts across multiple accounts coming from the same device or IP: When multiple login attempts for different accounts originate from the same device or IP address, it’s a strong indicator of a coordinated attack. This consistency suggests automated tools or bots are being used to execute the attack.
• A sudden increase in account lockouts or password reset requests: A spike in account lockouts or password reset requests can be a red flag for password spraying attempts. Attackers trigger these requests by repeatedly trying incorrect passwords.

In addition to the above indicators, advanced detection methods involve monitoring device attributes, network attributes, and behavioral biometrics to identify bot activity.

Upon detecting a password spraying attack, swift and decisive actions are a must to minimize damage. Here are the immediate steps to take:

1. Lock Affected Accounts and Reset Passwords

Immediately lock any accounts that show signs of suspicious activity to prevent further unauthorized access. Notify the affected users and require them to reset their passwords using strong, unique combinations. Implement multi-factor authentication (MFA) for additional security.

Tip: Ensure that password policies are updated to enforce complexity and prevent reuse. Consider taking steps towards going passwordless to eliminate passwords and thwart this attack vector for good.

2. Conduct a Thorough Investigation and Forensic Analysis

Initiate a detailed investigation to understand the scope and impact of the attack. Use forensic tools to analyze logs and identify how the attackers gained access, what data may have been compromised, and whether any other systems are affected. Preserve evidence for potential legal action and future reference.

Tip: Review and strengthen your security protocols to address identified vulnerabilities.

3. Notify Relevant Stakeholders and Law Enforcement if Necessary

Inform internal stakeholders, including IT, legal, and management teams, about the incident and actions being taken.

If sensitive data has been compromised, notify affected customers and comply with regulatory requirements for breach notification. In cases of significant breaches, contact law enforcement and provide them with all relevant information to assist in their investigation.

Tip: Maintain transparent communication with all parties to manage the situation effectively and maintain trust.

Proactive measures are essential to mitigate the risk of password spraying attacks. Implement the following strategies to enhance your organization's security:

• Enforce strong password policies and multi-factor authentication: Require users to create complex, unique passwords that are difficult to guess. Implement multi-factor authentication (MFA) or consider passwordless authentication methods to add an extra layer of security.
• Monitor and analyze login attempts for anomalies: Regularly review login attempts to detect unusual patterns or behaviors. Use security tools to flag and investigate any anomalies that might indicate a password spraying attack.
• Educate users on password security best practices: Conduct regular training sessions to inform users about the importance of strong passwords and the risks of password reuse. Encourage the use of password managers to help users securely manage complex passwords.
• Implement account lockout policies and rate limiting measures: Set policies to temporarily lock accounts after a certain number of failed login attempts. Use rate limiting to restrict the number of login attempts from a single IP address, making it harder for attackers to perform large-scale attacks.
• Utilize threat intelligence and security tools for early detection and response: Employ advanced security tools that leverage threat intelligence to detect and respond to password spraying attacks. These tools can provide real-time alerts and automated responses to potential threats.
• Utilize bot detection to identify and block automated activity: Use bot detection methods, such as behavioral biometrics, to spot and prevent automated activity. Since password spraying attacks are often automated, detecting bot-like behavior early can prevent successful breaches. Behavioral biometrics is an effective way to enhance bot detection capabilities.

Online fraud detection is becoming increasingly more important by the day. And that’s why 76% of security, IT, and business decision-makers name identity fraud as their highest priority in fraud prevention.

Ping Identity’s online fraud prevention solution is designed to protect your organization without damaging the user experience for good users. See how Ping can help you deliver secure employee and customer experiences in a rapidly evolving digital world.