Identification of Password Spraying

Password spraying is a type of cyber attack where the attacker attempts to access a large number of accounts using a few commonly used passwords. Unlike brute force attacks, which try many passwords against one user, password spraying targets many users with a few passwords. This method is often more effective at evading account lockout policies. From a penetration tester's perspective, identifying password spraying against a web application involves recognizing signs of this attack and understanding how it can be mitigated. Here are some key points and examples from a pentester's viewpoint:


  1. Suspicious Login Attempts: Monitor for an unusual number of failed login attempts, especially if they are spread across different user accounts but originate from the same IP address or a small set of IP addresses.
  2. Account Lockout Analysis: If the organization has an account lockout policy, a sudden increase in locked accounts might indicate a password spraying attempt.
  3. Unsuccessful Login Patterns: Look for patterns where there are repeated login attempts with commonly used passwords across various accounts.
  4. Traffic Analysis: Analyze network traffic for patterns that indicate automated login attempts, such as a high volume of requests to the login page from the same user agent or IP range.
  5. User Agent Consistency: Attackers often use scripts that have a static user agent string. Identifying numerous login attempts with the same user agent could signal a password spraying attack.
  6. Geographic Anomalies: Login attempts originating from geographic locations that do not align with the usual user activity can be suspicious.


  • Example 1: An attacker may try the password "Summer2023!" against all user accounts on a web application. If one of the accounts uses this password, the attacker gains access.
  • Example 2: A penetration tester notices that there are multiple login failures from different accounts but from the same IP address within a short time frame. This pattern is indicative of a password spraying attack.
  • Example 3: During a pentest, the tester observes that after trying a common password like "Password1", there is a noticeable increase in the number of account lockouts, suggesting that the common password was used in a password spraying attempt.


  1. Account Lockout Policies: Implement intelligent account lockout policies that lock out accounts after a few failed attempts but consider the risk of denial of service to legitimate users.
  2. Multi-factor Authentication (MFA): Enforcing MFA can significantly reduce the risk of successful password spraying.
  3. Password Policies: Encourage or enforce the use of complex, unique passwords that are not susceptible to simple spraying attacks.
  4. Monitoring and Alerting: Set up monitoring and alerting for unusual login patterns to quickly detect and respond to potential password spraying attacks.
  5. Education: Educate users about the importance of using unique passwords and the risks associated with using common passwords.

By identifying and understanding password spraying attacks, penetration testers can help organizations bolster their defenses against this subtle yet potentially dangerous threat.