What is Credential Stuffing?

Credential stuffing is a cyber attack where stolen account credentials are used to gain unauthorized access to user accounts across various platforms. This method exploits the common practice of password reuse across different services to break into accounts, making it a common threat in the digital age.

---

Credential stuffing operates by automating login requests using breached username and password pairs. This type of attack leverages large-scale automated tools that simulate a flood of login attempts, bypassing typical security measures like rate limiting or CAPTCHA by distributing the attempts across numerous IP addresses.

• Data Breach Source: Attackers obtain credentials from data breaches, where large volumes of personal data are illegally accessed and sold.
• Automation: Specialized software automates the login attempts across various websites, testing the stolen credentials en masse.
• Success Rates: Despite low success rates per attempt, the sheer volume of attempts can make this attack method lucrative.

• Password Reuse: Many users employ the same password across multiple sites, increasing vulnerability.
• Advanced Bots: Modern bots can mimic human login patterns, making them harder to detect.
• Volume of Attacks: Millions of attempts can statistically secure access to thousands of accounts.

Businesses and individuals can significantly reduce the risk of credential stuffing by implementing and adhering to robust security practices:

• Unique Passwords: Encourage or enforce the use of unique passwords for each service.
• Two-Factor Authentication (2FA): Adding a second layer of security can effectively neutralize the risk posed by compromised passwords. Passkeys are also a more secure alternative.
• Awareness and Education: Regularly inform users about the importance of security best practices.

---

• Credential stuffing uses pre-existing username and password combinations, while brute force attacks attempt to guess passwords without prior knowledge.

• Always use unique passwords for different sites and enable two-factor authentication wherever available.

• Bots automate the login attempts, using varying IPs and device identifiers to mask the attack, making them look like legitimate user traffic.