> For the complete documentation index, see [llms.txt](https://hacking-notes.jord4n.pro/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://hacking-notes.jord4n.pro/web/authentication/username-enumeration-via-different-responses.md).
# Username Enumeration via Different Responses
Username Enumeration via Different Responses notes for PortSwigger Web Security Academy labs, including exploitation workflow, payload testing, Burp Suite validation, and remediation context.
### Username Enumeration via Different Responses
The site is vulnerable to:
* enumeration of user names via different response messages;
* the gross-force password.
The aim is:
1. Find a valid username from a wordlist.
2. Brute-force the associated password, from another wordlist.
3. Log in and access the user account page.
#### Setup
* The site offers a classic **login** form.
* There are lists of **usernames** and **passwords** provided by the lab.
* The connection request is intercepted to send to **Burp Intruder**.
#### 1. User List
1. Intercept a connection attempt and send it to **Intruder**.
2. Place a payload on the **username** parameter.
* Load the **wordlist of users** provided by the lab.
1. Launch the attack and observe the answers (statute, length, etc.).
Note that for the user name **`apollo`**, the answer has a different **length** from the others.
→ This indicates that **`apollo`** is a valid **username**.
#### 2. Brute Password Strength
1. Resume the login request with **username fixed to `apollo`**.
2. Send the query again in **Intruder**.
3. Place the payload this time on the **password** parameter.
4. Load the **passwordlist** provided.
5. Launch the attack and analyze the answers.
The **`mustang`** password produces a different **response** (e.g. length or content) indicating a successful **connection**.
#### 3. Final Login
Valid credentials are:
* **Username :** `apollo`
* **Password :** `mustang`
---
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