Lab: Broken brute-force protection, multiple credentials per request
Summary: PortSwigger's Web Security Academy lab describes a login endpoint that accepts credentials in JSON and whose brute-force protection has a logic flaw: submitting the password field as an array of candidate strings in a single POST /login request returns a 302 response that logs the attacker in as the user carlos. The lab's stated goal is to brute-force carlos's password this way and then open his account page.
Bottom line: The protection here fails because it counts requests rather than the credentials inside them, so a single request carrying an array of passwords slips past a control built to stop repeated attempts against one account.
Read the original at PortSwigger Research ↗
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