Cyberattacks continue to evolve, becoming more sophisticated and, in many cases, harder to detect. One method that has gained significant traction among cybercriminals is password spraying. Unlike traditional brute force attacks, where attackers repeatedly try to crack one account by guessing passwords, password spraying is a more subtle approach. Here’s what you need to know about this tactic, how it works, and how to protect against it.
What is Password Spraying?
Password spraying is a type of attack where cybercriminals attempt a single, commonly used password (like “password123” or “welcome1”) across many different user accounts, rather than focusing multiple password attempts on one account. This method helps attackers avoid detection by traditional security mechanisms, which often lock accounts after multiple failed attempts in a short period.
In a password spray attack, the focus is on leveraging weak passwords across many accounts, relying on users who may still be using default or easy-to-guess passwords.
How Password Spraying Works
- Preparation: Attackers begin by gathering a list of usernames, which can be obtained through data breaches, publicly accessible online databases, or by scraping data from corporate directories or social media.
- Choosing Common Passwords: The attackers then select a handful of commonly used or default passwords, such as “123456,” “password,” or “qwerty.” The idea is to try simple, frequently used passwords rather than complex combinations.
- Execution: Instead of targeting a single account, attackers attempt to log into multiple accounts using the same password. They may wait a significant period between attempts to avoid detection by intrusion prevention systems or lockout mechanisms.
- Access: If successful, attackers gain access to the user account and can leverage it for further exploitation, such as data exfiltration, lateral movement within a network, or accessing sensitive information.
Why Password Spraying Works
Password spraying exploits a common weakness: the tendency of users to choose simple, easily remembered passwords. While organizations increasingly enforce password policies, employees or customers may still use predictable passwords. In addition, password spraying works well because it flies under the radar of traditional security systems, avoiding detection by using fewer attempts per account over time.
Real-World Examples
Several recent high-profile attacks have utilized password spraying tactics:
- Storm-0940: In October 2024, Microsoft highlighted how this Chinese threat actor used password spray attacks through a covert network to target multiple organizations. By leveraging common passwords, Storm-0940 was able to access accounts without triggering traditional security alarms.
- Credential Stuffing and Password Spraying Combined: Many cybercriminals combine password spraying with credential stuffing, where previously breached usernames and passwords are tested against new accounts to exploit users who reuse passwords across services.
How to Protect Against Password Spraying
- Implement Multi-Factor Authentication (MFA): One of the most effective defenses is to require an additional authentication factor beyond the password. Even if an attacker guesses the correct password, they will still be blocked by the MFA prompt.
- Educate and Enforce Strong Password Policies: Organizations should mandate the use of complex, unique passwords and educate employees on password hygiene. Encourage the use of password managers to help users create and store complex passwords without relying on easy-to-remember options.
- Monitor for Unusual Login Behavior: Security information and event management (SIEM) systems can flag unusual patterns, such as repeated login attempts across multiple accounts or logins from unfamiliar locations.
- Account Lockout Policies: While some lockout mechanisms are bypassed by password spraying, more sophisticated solutions can recognize suspicious behavior patterns across user accounts, triggering alerts or limiting access attempts.
- Leverage Threat Intelligence: Keeping up with threat intelligence reports can help organizations understand emerging tactics, like password spraying, and proactively implement measures against known threat actors and techniques.
Password Spraying and the Future of Cybersecurity
As attackers continue to refine their techniques, cybersecurity defenses must evolve in tandem. Password spraying is a reminder of how a combination of weak passwords, user behavior, and traditional detection systems can create vulnerabilities. By adopting best practices, leveraging advanced security tools, and staying informed on emerging threats, organizations can mitigate the risks posed by password spray attacks.
Conclusion
Password spraying highlights a fundamental weakness in cybersecurity: reliance on passwords alone. As organizations transition to more robust authentication methods and continue to educate users, the impact of password spray attacks can be minimized. By understanding this technique and proactively implementing defenses, companies can stay one step ahead of attackers.