ELI5: What is Password Spraying?

Instead of guessing one person’s password a hundred times (which gets you locked out), the attacker tries one common password like “Password1” on a hundred different accounts.

Definition

Password spraying is an attack technique that inverts traditional brute-force: instead of trying many passwords against one account (which triggers lockout), the attacker tries a very small number of commonly used passwords (often just one or two) against a large number of different accounts. This stays below lockout thresholds per account while still achieving successful logins for accounts with weak passwords.

Key Details

  • Lockout evasion: Tries only 1-3 passwords per account per time period—stays below the lockout threshold (typically 5-10 failures).
  • Common spray passwords: SeasonYear! (Summer2024!), CompanyName1, Password1, Welcome1.
  • Highly effective in environments with weak password policies or no MFA.
  • Detection: many accounts receiving exactly 1-2 failed login attempts within a short window—unusual pattern.
  • MFA is the most effective defense—a correct password is insufficient without the second factor.

Connections