What is password spraying?

Password spraying is a type of brute-force attack and account takeover tactic in which hackers test frequently used and easy-to-guess passwords over multiple targeted accounts. Unlike traditional brute-force attacks that focus on a single account, password spraying minimizes detection by using low-frequency login attempts spread over time and across different user accounts.

In a password spraying attack, a cybercriminal “sprays” one or more common passwords over a list of targeted usernames. The malicious attacker first purchases or obtains a list of usernames from previous breaches or data leaks, sometimes creating a list based on common default username formats. The attacker then selects a set of commonly used passwords (e.g., “”password123,” ”“welcome,” or” 123456”) and rotates through multiple usernames, trying only a few passwords at once to evade lockout mechanisms that would detect too many failed attempts in a short period. Attackers frequently employ botnets to carry out these attacks.

• Horizontal spraying. Attackers try the same password across multiple accounts within an organization or domain to find weak credentials.
• Vertical spraying. Attackers test a wide range of common passwords against a small set of accounts. This method is riskier than horizontal spraying, as it’s more likely to trigger lockout mechanisms.
• Credential stuffing. Credential stuffing attacks, in which attackers break into accounts using previously stolen login data from data breaches, can be used in combination with password spraying tactics if attackers have usernames but lack their associated passwords.

Password spraying can lead to unauthorized access to accounts and data breaches. For businesses, this often means attackers gain access to user accounts, potentially compromising sensitive customer data or disrupting access to services.  These attacks can erode customer trust and tarnish a company’s reputation, especially if attackers use compromised accounts for malicious activities such as spam or fraud.

Businesses can reduce the risk of breaches and protect user accounts from password spraying using various defense and protection protocols, including multifactor authentication (MFA), strong password requirements, and login attempt monitoring using tools that detect multiple login failures or by rate-limiting.

User education is also crucial, and companies should inform users of the importance of complex passwords, so that they do not compromise the privacy of their accounts.

However, while password hygiene education is important, effective cybersecurity should not place full responsibility on users. Additional protective measures, including behavioral analysis and threat intelligence to detect stolen credentials, are also important tools for preventing account takeovers.

HUMAN’s Account Takeover Defense stops automated attacks by blocking mass credential stuffing, cracking attempts, and neutralizing stolen or breached credentials. Sophisticated bots are intercepted at the account perimeter, while advanced threat intelligence analyzes compromised credentials from the latest breaches and attacks. This allows security teams to spend less time investigating account takeover incidents and more time on mission-critical tasks.

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• Why account security doesn’t stop at login
• What is a brute force attack? | Definition, types, & prevention