In reviewing logs, what type of attack could a security analyst be observing if there are indications of repeated failed authentication attempts?

The scenario of observing repeated failed authentication attempts in logs typically points to a systematic effort to guess or crack a password using a predefined list of possible passwords. This is most characteristic of a dictionary attack, where an attacker utilizes a list of common passwords and attempts to gain access by sequentially trying each one until an account is successfully accessed or blocked after a certain number of attempts.

In contrast, while a password-spraying attack also involves multiple failed login attempts, it is characterized by using a small set of common passwords across many different accounts rather than continuously trying different passwords on a single account. Hence, the behavior you would observe in the logs would differ, as repeated failures would be less focused on a single account in the case of password-spraying.

Similarly, a rainbow table attack employs precomputed tables of hashes to reverse-engineer passwords, and while it may also involve multiple attempts, it is not typically associated with repeated failed authentication logs in the same manner as a dictionary attack. A keylogger attack does not relate to authentication attempts at all; instead, it records keystrokes to capture passwords without the need for repeated login attempts.

Therefore, the indication of repeated failed authentication attempts is most aligned with a dictionary attack, where the attacker's goal is