Password spraying is a type of cyberattack where threat actors attempt to gain unauthorized access to a large number of accounts by systematically trying a few commonly used passwords against many usernames. Unlike traditional brute force attacks that target a single account with numerous password guesses, password spraying spreads the attempts across multiple accounts, reducing the risk of detection and account lockout.

According to the Cybersecurity and Infrastructure Security Agency (CISA), password spraying attacks have increased in frequency, targeting organizations of all sizes and sectors.

While both password spraying and brute force attacks aim to compromise accounts, their methodologies differ significantly:

• Brute force attacks focus on a single account, rapidly cycling through thousands of password combinations. This often triggers account lockout mechanisms.
• Password spraying targets many accounts, using a small set of common passwords (like “Password123” or “Welcome1”). By limiting the number of attempts per account, attackers evade lockout policies and detection systems.

The subtlety of password spraying makes it a favored tactic for attackers seeking to avoid triggering security alarms and account lockouts.

Attackers leverage password spraying tactics because they exploit the human tendency to use weak or default passwords across multiple accounts. This approach is especially effective against organizations with large user bases and inadequate password policies. Common targets include:

• Corporate email accounts (e.g., Office 365, Google Workspace)
• Remote access portals (VPN, RDP, Citrix)
• Cloud services and SaaS platforms
• Legacy systems with weak authentication controls

The Microsoft Security Team reports that password spraying is one of the most common techniques used to compromise enterprise accounts.

Account lockouts are a double-edged sword. While they protect against unauthorized access, they can also disrupt legitimate users, especially during a password spraying attack. Risks include:

• Denial of Service (DoS): Attackers may intentionally trigger lockouts, causing widespread disruption.
• Operational Downtime: Locked accounts can halt business operations, impacting productivity and customer service.
• Increased Helpdesk Load: IT support teams may be overwhelmed with password reset requests.

Balancing security and usability is crucial to prevent attackers from leveraging lockout mechanisms as a weapon.

Attackers use various patterns and automated tools to conduct password spraying attacks efficiently. Common techniques include:

• Slow and Low: Limiting login attempts per account to avoid detection and lockouts.
• Automated Scripts: Tools like SprayingToolkit, CrackMapExec, and Spray automate the process, targeting thousands of accounts with minimal effort.
• Targeted Password Lists: Using lists of the most common or organization-specific passwords.
• Timing Attacks: Spreading attempts over hours or days to evade rate-limiting controls.

These tools and tactics are widely available and require minimal technical expertise, making password spraying a low-barrier threat. For more on the underlying approaches, see the guide to wordlist attacks and how attackers build effective password lists.

Weak or outdated password policies are a primary enabler of password spraying. Attackers exploit:

• Short or Simple Passwords: Policies that allow passwords like “Summer2024” or “Company123”.
• Lack of Complexity Requirements: Absence of rules for uppercase, lowercase, numbers, and symbols.
• Default or Shared Passwords: Use of vendor-supplied or reused passwords across accounts.
• Infrequent Password Changes: Long intervals between required password updates.

According to NIST SP 800-63B, organizations should enforce strong password creation and avoid common, easily guessed passwords to reduce susceptibility to spraying attacks. Regular password audits and recovery testing can help identify accounts that are especially vulnerable to these tactics.

Early detection of password spraying tactics is vital. Common indicators include:

• Multiple failed login attempts across different accounts within a short timeframe.
• Successful logins from unusual locations or IP addresses.
• Sudden spike in account lockouts or password reset requests.
• Unusual activity in audit logs, such as attempts to access sensitive resources.

The MITRE ATT&CK Framework provides detailed guidance on detecting and mitigating password spraying attacks.

Effective log analysis is essential for identifying password spraying attempts. Key steps include:

• Reviewing authentication logs for patterns of failed logins distributed across many accounts.
• Correlating login attempts with geolocation and device fingerprinting data.
• Setting up alerts for anomalous login behavior, such as access from new devices or regions.
• Leveraging Security Information and Event Management (SIEM) solutions for real-time monitoring.

For more on log analysis best practices, see the SANS Institute Log Analysis Guide, and consider leveraging SIEM fundamentals for a quick start in security event monitoring.

The most effective defense against password spraying tactics is a robust authentication strategy. Key measures include:

• Multi-Factor Authentication (MFA): Requiring a second form of verification drastically reduces the success rate of password spraying attacks. According to CrowdStrike, MFA can block over 99% of automated attacks.
• Strong Password Requirements: Enforce minimum length, complexity, and prohibit the use of common passwords. Reference CIS Controls for best practices.
• Password Blacklists: Prevent users from selecting passwords found in breach databases or known to be commonly used.

A layered authentication approach significantly reduces the risk of compromise. For a deeper dive into how password length and complexity impact security, see Password Length vs Complexity: Which Matters More?

Account lockout policies are a traditional defense, but must be carefully configured to avoid denial-of-service risks. Recommendations include:

• Thresholds: Set reasonable thresholds for failed login attempts (e.g., 5-10 attempts) before lockout.
• Lockout Duration: Use temporary lockouts (e.g., 15-30 minutes) rather than permanent disables.
• Progressive Delays: Increase the delay between login attempts after each failure.
• Alerting: Notify users and administrators of lockouts or suspicious activity.

For guidance, see OWASP Authentication Cheat Sheet. You can also learn how to configure a bruteforce attack for security testing, which can help organizations calibrate their lockout policies against real-world attack scenarios.

Continuous monitoring is essential to detect and respond to password spraying tactics in real time. Best practices include:

• Deploying SIEM solutions to aggregate and analyze authentication logs.
• Configuring alerts for patterns indicative of spraying (e.g., multiple failed attempts across many accounts).
• Integrating threat intelligence feeds to identify known attacker IPs and behaviors.
• Regularly reviewing and tuning detection rules to minimize false positives.

For more on monitoring strategies, refer to CrowdStrike Security Monitoring.

A secure password recovery process is critical to prevent attackers from exploiting account reset mechanisms during or after a password spraying attack. Recommendations include:

• Identity Verification: Require multi-factor authentication or out-of-band verification (e.g., SMS, email, or phone call) before allowing a password reset.
• One-Time Links: Use expiring, single-use links for password reset emails.
• Audit Trails: Maintain logs of all password reset requests and actions for forensic analysis.
• Rate Limiting: Limit the number of password reset attempts per user and per IP address.

For detailed guidance, see OWASP Forgot Password Cheat Sheet. Organizations can also benefit from understanding secure implementation of password reset tokens to further protect recovery workflows.

During password recovery, it’s important to avoid inadvertently locking out legitimate users. Strategies include:

• Grace Periods: Allow a short window for users to complete the reset process without triggering lockouts.
• Temporary Access Tokens: Provide time-limited access tokens to facilitate secure recovery.
• Support Channels: Offer alternative verification methods (e.g., helpdesk support) for users unable to complete automated recovery.
• Communication: Clearly inform users of the recovery process and any lockout risks.

Balancing security and user experience is essential for effective password recovery in the context of password spraying tactics.

End users are often the weakest link in the security chain. Regular training can dramatically reduce the effectiveness of password spraying tactics. Training topics should include:

• Recognizing phishing attempts and suspicious login prompts.
• Understanding the importance of strong, unique passwords for each account.
• How to report suspected security incidents or lockouts.
• Safe password reset and recovery procedures.

The ISACA Password Spraying Guide offers additional resources for user education.

Promoting good password hygiene is a frontline defense against password spraying tactics. Best practices include:

• Using passphrases or password managers to generate and store complex passwords.
• Never reusing passwords across different accounts or services.
• Regularly updating passwords, especially after a suspected compromise.
• Enabling MFA wherever possible.

For more on password hygiene, refer to NCSC Top Tips for Staying Secure Online or try an online password security checker to assess the strength of your chosen passwords.

If you suspect a password spraying attack, immediate action is essential to minimize damage:

• Containment: Temporarily disable affected accounts or restrict access to sensitive systems.
• Force Password Resets: Require users to change passwords, prioritizing those with weak or compromised credentials.
• Investigate: Analyze logs to determine the scope and source of the attack.
• Notify: Inform users and stakeholders of the incident and provide guidance on next steps.

Refer to the FIRST CSIRT Services Framework for incident response best practices.

After containing the immediate threat, focus on long-term remediation to prevent recurrence:

• Review and Update Policies: Strengthen password and authentication policies based on lessons learned.
• Enhance Monitoring: Implement advanced detection and alerting for future attacks.
• Conduct User Training: Reinforce security awareness and password hygiene.
• Collaborate with Law Enforcement: Report significant incidents to authorities such as the IC3.

Ongoing vigilance is key to maintaining a resilient security posture against password spraying tactics.

Password spraying tactics represent a persistent and evolving threat to organizations and individuals. By understanding how these attacks work, recognizing their signs, and implementing robust prevention and recovery strategies, you can significantly reduce the risk of account compromise and lockouts. Prioritizing strong authentication, user education, and proactive monitoring will help ensure your accounts remain secure, even in the face of sophisticated password spraying attacks.

• CISA: Password Spraying Attacks
• MITRE ATT&CK: Password Spraying
• Microsoft: Defending Against Password Spray Attacks
• NIST SP 800-63B: Digital Identity Guidelines
• OWASP Authentication Cheat Sheet
• CrowdStrike: Password Spraying Explained
• SANS Institute: Log Analysis Guide
• ISACA: Password Spraying Attacks and How to Prevent Them
• NCSC: Top Tips for Staying Secure Online
• IC3: Internet Crime Complaint Center
• Details about Wordlist Attacks
• How Secure is this password?