What action should a developer implement to strengthen authentication security against broken authentication?

Implementing multifactor authentication (MFA) is an effective strategy to enhance authentication security, particularly against risks associated with broken authentication. MFA requires users to provide two or more verification factors to gain access to an account or system. This adds an additional layer of security beyond just a username and password.

In the event that a user's password is compromised, MFA can prevent unauthorized access, as the attacker would still need the second factor, which could be something they possess (like a smartphone with an authentication app or SMS code), something they know (like a pin), or something inherent to them (like a fingerprint). By requiring this combination of factors, the system significantly reduces the likelihood of unauthorized access, making it much harder for attackers to exploit compromised credentials.

While the other options may enhance security in other areas of the system, they do not specifically address the vulnerabilities related to broken authentication. For instance, enabling Address Space Layout Randomization (ASLR) primarily helps mitigate memory corruption vulnerabilities, and setting limits typically addresses denial-of-service attacks rather than strengthening authentication. Similarly, although performing a password check is essential, it alone does not provide the additional security required to protect against compromised credentials. MFA remains the most effective solution for reinforcing authentication processes against various threats.