Lab: Username enumeration via different responses
Summary: PortSwigger's lab is deliberately vulnerable to username enumeration and password brute-force attacks, and contains an account with a predictable username and password drawn from supplied wordlists. Solving it requires enumerating a valid username, brute-forcing that user's password, then logging in to reach the account page.
Why it matters: The lab's own guidance notes that enumerating a valid username first is generally far more efficient than a single cluster bomb attack, which is the same asymmetry an attacker gets against any login form that answers differently for valid and invalid usernames.
Read the original at PortSwigger Research ↗
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