Username enumeration is a typical application vulnerability that happens when an attacker determines whether or not usernames are genuine. This problem most typically happens on login forms, when an error similar to “the username is incorrect” is returned.
An attacker can take advantage of this behavior by observing the application’s reaction to a long list of frequent usernames, recognized names, and dictionary terms. The attacker can then deduce which usernames are valid based on the findings.
An attacker can use the detected usernames to look for passwords in already hacked databases. Your users most likely have identical usernames on other sites and may have used the same passwords.
ZOFixer.com security scan helps to find this vulnerability in your software and server, you can easily use it by registering on our website and activating the 30-day trial.