Password spraying is a type of brute-force cyberattack, but with a twist that makes it stealthier and more effective against large organizations. Here’s a breakdown:

🔓 What Is Password Spraying?

• Instead of trying many passwords on one account (which triggers lockouts), attackers try one or a few common passwords across many accounts.
• This method avoids detection by not exceeding login attempt limits on individual accounts.

🧠 How It Works

1. Gather usernames: Attackers compile a list of valid usernames (often from public sources or data breaches).
2. Choose common passwords: They use widely known passwords like 123456, Password123, or qwerty.
3. Attempt logins: The attacker tries logging into each account using the same password.
4. Repeat with new passwords: If unsuccessful, they try another common password across all accounts.

This technique is explained in detail by CrowdStrike.

⚠️ Why It’s Dangerous

• Harder to detect: It bypasses traditional brute-force protections.
• Targets weak password habits: Many users reuse simple passwords.
• Can lead to privilege escalation: Once inside, attackers may gain access to sensitive systems.

According to SentinelOne, over half of users reuse passwords, making this attack highly effective.

🛡️ How to Prevent It

• Enforce strong password policies (length, complexity, uniqueness).
• Use multi-factor authentication (MFA).
• Monitor for unusual login patterns (e.g., many failed attempts across accounts).
• Educate users about password hygiene.
• Implement account lockout policies with caution—too strict can help attackers identify valid usernames.

For a full prevention checklist, Microsoft offers a Password Spray Investigation Guide.