Broken Brute-Force Protection, IP Block
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Upon visiting the login page, entering arbitrary credentials results in a rate-limiting error after multiple failed attempts, stating that you must wait 1 minute.
By testing further, I observed:
The counter resets after a successful login.
If I attempt two failed logins for one user and successfully log in as another user (wiener), the lockout mechanism resets for future attempts.
This behavior reveals a logic flaw in the brute-force protection:
The system resets the counter upon a successful login, allowing us to alternate between two users to bypass the lockout.
To exploit this logic flaw:
Use the victim's username (carlos
) and attempt to brute-force their password.
Alternate the password attempts for carlos
with a known valid login (wiener:peter
) to avoid the lockout.
Modify the password list to repeat wiener's password after every incorrect attempt:
We use the provided password list and modify it to use wieners password after each line to trigger a successful login
Once the attack finishes:
Filter results for carlos
and status code 302 Redirect.
The 302 status code indicates a successful login, revealing the correct password for carlos
And then we can see carlos's
password