# Back End Components & Vulns

| Code                        | Description                                                                                                         |
| --------------------------- | ------------------------------------------------------------------------------------------------------------------- |
| **Successful responses**    |                                                                                                                     |
| `200 OK`                    | The request has succeeded                                                                                           |
| **Redirection messages**    |                                                                                                                     |
| `301 Moved Permanently`     | The URL of the requested resource has been changed permanently                                                      |
| `302 Found`                 | The URL of the requested resource has been changed temporarily                                                      |
| **Client error responses**  |                                                                                                                     |
| `400 Bad Request`           | The server could not understand the request due to invalid syntax                                                   |
| `401 Unauthorized`          | Unauthenticated attempt to access page                                                                              |
| `403 Forbidden`             | The client does not have access rights to the content                                                               |
| `404 Not Found`             | The server can not find the requested resource                                                                      |
| `405 Method Not Allowed`    | The request method is known by the server but has been disabled and cannot be used                                  |
| `408 Request Timeout`       | This response is sent on an idle connection by some servers, even without any previous request by the client        |
| **Server error responses**  |                                                                                                                     |
| `500 Internal Server Error` | The server has encountered a situation it doesn't know how to handle                                                |
| `502 Bad Gateway`           | The server, while working as a gateway to get a response needed to handle the request, received an invalid response |
| `504 Gateway Timeout`       | The server is acting as a gateway and cannot get a response in time                                                 |

Once we identify the web application version, we can search Google for public exploits for this version of the web application. We can also utilize online exploit databases, like [Exploit DB](https://www.exploit-db.com/), [Rapid7 DB](https://www.rapid7.com/db/), or [Vulnerability Lab](https://www.vulnerability-lab.com/). The following example shows a search for WordPress public exploits in [Rapid7 DB](https://www.rapid7.com/db/)

<figure><img src="/files/CPK8pGuQfiUkmTt2Sr6n" alt=""><figcaption></figcaption></figure>


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