Complete Guide to BurpSuite Intruder | TryHackMe Junior Penetration Tester

Intruder is Burp Suite’s built-in fuzzing tool that allows for automated request modification and repetitive testing with variations in input values. By using a captured request (often from the Proxy module), Intruder can send multiple requests with slightly altered values based on user-defined configurations. It serves various purposes, such as brute-forcing login forms by substituting username and password fields with values from a wordlist or performing fuzzing attacks using wordlists to test subdirectories, endpoints, or virtual hosts. Intruder’s functionality is comparable to command-line tools like Wfuzz or ffuf.

However, it’s important to note that while Intruder can be used with Burp Community Edition, it is rate-limited, significantly reducing its speed compared to Burp Professional. This limitation often leads security practitioners to rely on other tools for fuzzing and brute-forcing. Nonetheless, Intruder remains a valuable tool and is worth learning how to use it effectively.

There are four sub-tabs within Intruder:

• Positions: This tab allows us to select an attack type (which we will cover in a future task) and configure where we want to insert our payloads in the request template.
• Payloads: Here we can select values to insert into the positions defined in the Positions tab. We have various payload options, such as loading items from a wordlist. The way these payloads are inserted into the template depends on the attack type chosen in the Positions tab. The Payloads tab also enables us to modify Intruder’s behavior regarding payloads, such as defining pre-processing rules for each payload (e.g., adding a prefix or suffix, performing match and replace, or skipping payloads based on a defined regex).
• Resource Pool: This tab is not particularly useful in the Burp Community Edition. It allows for resource allocation among various automated tasks in Burp Professional. Without access to these automated tasks, this tab is of limited importance.
• Settings: This tab allows us to configure attack behavior. It primarily deals with how Burp handles results and the attack itself. For instance, we can flag requests containing specific text or define Burp’s response to redirect (3xx) responses.