We won’t introduce any new vulnerabilities we haven’t talked about already. We will here examine one key element in the effective methodology for hacking web apps. It will be all about the use of automation to strengthen and also to accelerate the customized attacks. There are the range of techniques which are involved that can be applied throughout the app and to every stage of the attack process that happens, from initial mapping to the actual exploitation.
Also, we are well introduced that there is difference between every web application. So, attacking the web app involves using a variable number of manual procedures and techniques to help you understand its behavior and probe for vulnerabilities. Also, it entails bringing to bear your experience and the intuition in an imaginative way. It is well known here that the attacks are customized in nature. They are also tailored to the practical behavior you have identified and also to the specific ways in which the app enables you to interact with and to manipulate it. We will here describe a proven methodology for automating the customized attacks. And, before we do that, if this topic disturbed you, you need to read more about the cyber security tips and the internet security tips.
User for Customized Automation
There exist three main situations in which the customized automated techniques may be employed in the order to help you to attack the web app. Those are:
1.The enumerating identifiers. It is well known that the most apps use the various names and the identifiers for referring to individual items of the data and resources, which may be the account numbers, some usernames, or even document IDs. You will need to iterate through a large number of the potential identifiers for the enumerating which one is valid and worthy of the further investigation. Also, when you come in this situation, you can besides all use automatic and fully customized way to work through the list of the possible identifiers or even cycle through the syntactic range of the identifiers which are believed to be in the use of the app.
2.Harvesting data. This is the second one. There are the many kinds of the app’s vulnerabilities which enable you to extract some useful or even sensitive data from the app by using the specifically crafted requests.
3.Web app fuzzing. Above all we have explained, your initial mapping exercise may identify dozens of the distinct requests you need to probe. The each of them is containing the numerous different parameters. So yes, the testing each case can manually be time-consuming and mind-numbing, and also it could leave a large part of the attacks surface neglected. So, what can you do? In this situation, you can use the quickly generating huge numbers of requests which are containing common attack strings and quickly access the server’s responses in a purpose to hone it on the interesting cases which merit a further investigation you will need. So yes, this is called fuzzing.
Enumerating Valid Identifiers
The first one is the basic approach. This is a task of formatting customized automated attack for enumerating the valid identifiers. Also, locating a request or a response pair which is following some special characteristics:
-the request has to include a parameter which contains the identifier you are targeting ;
-a server’s response for that request varies in a systematic way when you vary the parameter’s value.
Scripting the Attack
Let’s suppose that you have validated the following URL, which has returned as a 200 status code when a valid PageNo value is submitted and a 500 status code otherwise. So, that request or a response pair satisfies the two conditions which are required for you to be able to amount the automated attack to enumerate a valid page IDs.
Because this is a very simple case, it is possible to create a custom script quickly for performing the automated attack. Also, the same results can be achieved with the Windows batch script.
So, yes, the simple scripts are ideal for performing a straightforward task such as cycling through a list of parameter values and parsing the server’s response for a single attribute. Although, there are many situations in which you will be likely to require more power and flexibility than just a command-line scripting which can readily offer.
JAttack
This is the name of the simple but versatile tool that demonstrates how anyone with some basic programming knowledge can use the customized automation for delivering the powerful attacks against an app. This ‘tool’ understands the concept of a requested parameter. There are many situations where the request contains the parameters we often don’t want to modify in the given attack, but that we still need to include for the attack to be successful. So, can be used the ”attack” field to flag whether a given parameter is being subjected to the modification in the current attack.
Here we need our tool to understand the concept of an attack payload. Because there are the different types of the attacks, we need to create the different payload sources.
Harvesting Useful Data
This is the second main use of the customized automation when attacking an app is to extract the useful or sensitive data. And that all by using specifically crafted requests for retrieving the information of one item at a time. So, this situation commonly arises when you have already identified an exploitable vulnerability, such as an access control flaw, which enables you to access the unauthorized resource by specifying an identifier for it. But, it may also arise when the app is functioning entirely as it was intended by its designers.
The automated data harvesting may be useful:
-when an online retailing app contains a facility for registered customers to view their pending orders ;
-if a forgotten password function relies on a user-configurable challenge ;
-when a work flow app contains a function for displaying some basic account information about a given user, including her the privilege level within the app.
Fuzzing for Common Vulnerabilities
This is the third main use of customized automation. It does not involve the targeting of any known vulnerability for enumerating or extracting the information. Here, your objective is to probe the app with various crafted attack strings which are designed to cause the anomalous behavior within the app in the particular common vulnerabilities are present. This kind of the attack involves submitting the same set of the attack payloads as every parameter to every page of the app, regardless of the normal function of each parameter or the type of data the app expects to receive. The payload is also known as fuzz strings.
Also, in this situation, you generally need to capture as much detail as possible in the clear form. In that case, you can easily review this information for identifying the causes where your attack strings have triggered some anomalous behavior within the app which merits further investigation.
Barriers to Automation
The techniques we described so far can be applied without any complications in many applications. Although, there are the cases in which you may encounter the various obstacles which prevent you from straight forwardly performing customized automated attacks. Those barriers may be put into two categories:
1.Session-handling mechanisms. These mechanisms defensively terminate the sessions in response to unexpected requests, employ ephemeral parameter values for an example anti-CSRF tokens which change per request. Also, they may involve the multistage processes.
2.CAPTCHA. This control is designed to prevent the automated tools from accessing a particular app function, which may be such a function as to register now the new users.
So, what have we learned today? I think very much. This topic was a bit different, so I am glad if you understood it well. We saw that when you are attacking the web app, there is the majority of the necessary tasks which need to be tailored to that app’s behavior and the methods by which it actually enables you to interact with and manipulate it. So yes, you will often find yourself working manually, submitting individually crafted requests and reviewing the app’s responses.
Also, the techniques we described here are conceptually initiative. Involving the leveraging automation to make these customized tasks faster, easier, and of course more effective. Well, it is possible to automate virtually any manual procedure you want to carry out by using the power and the reliability of your own computer for the attack and for locating the target’s defects and weak points. But of course, there are the cases in which the obstacles exist. Those prevent you from straightforwardly applying the automated techniques. But in most cases, they can be overcome either by refining your automated tools or by finding a weakness in the app’s defenses.
But not to forget, using the customized automation effectively requires the experience, skills and of course the imagination. Although, you can use the tools for help, or you can write your own one. But, always remember, that there is no substitute for the human intelligence.