Username enumeration is a type of vulnerability in web applications, where it is possible to find exact usernames or to confirm that a guessed (or leaked) username exists in the system based on system response.
There are many web applications in the world, each of which has vulnerabilities due to developer errors, and this is a problem for all of them, and even the best of them, like the "Adobe Connect" program, have vulnerabilities that occur every month. They are found and fixed by the team. With the disclosure of the admin username, one of the most important steps in the field of targeted hacking can be taken, and as a result, the hacker can more easily achieve his desire, which may be destruction or ransomware attack or infection.
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