Learn Kali Linux 2019

User enumeration through noisy authentication controls

Enumeration is the technique in which a hacker or a penetration tester attempts to perform a brute-force attack to either guess or confirm valid users on a target system. A simple example is where a malicious user or a penetration tester performs a password-guessing or brute-force attack on an email portal.

The following is an example of a typical login portal. The credentials shown in the following screenshot are an example and are not real:

An attacker can attempt various combinations of possible usernames and passwords until a valid user is found. However, such attacks are considered ...