Category Archives: Web Security

Back Refresh Attack on QualysGuard- Your browser’s back button can do more than you think !!


Hello Guys !! Hope the new year started good for you all. 

Continuing my previous statement of "sometimes functionality leads to vulnerability..", I am gonna start discussing this another feature of the browser which can lead to leaking sensitive information like your passwords and sometimes even you complete Credit Card details. Definitely there are scenarios and certain dependencies which we will go though in later in the post.

What Actually it is !!

As you have already noticed the back and forward buttons of the browsers, these buttons simply navigate you to through the pages you have visited during your browsing history. So definitely browsers have the ability to maintain a recent record of pages that were visited by a user. The back and forward button on browsers use this functionality to display the pages recently browsed. In addition browsers also keep track of variables that were sent to server(Even by a POST Request) while you fetched any page.

These attractive feature enhances the user experience definitely but can be very harmful if the applications are insecurely written. 

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CSV Macro Injection : It’s rather a trick to abuse the functionality…

Application security is quite a tricky domain. Just imagine for all those years when you thought something as a functionality of the application and suddenly it turns out to be a vulnerability which can be exploited to take down your system completely.

CSV Macro Injection/Formula Injection is also one of those. We will look into it in detail that how a simple and such useful feature can become vulnerable and abuse the complete CIA triangle.

We can't deny the usefulness of spreadsheets in our daily IT/Non-IT life. If you have bulk data and you want it to edit, sort, represent, compute(we really can do more stuffs than this as well) repetitively the excel and CSV is the correct file format for you. In computing, a comma-separated values (CSV) file stores tabular data (numbers and text) in plain text. Each line of the file is a data record. Each record consists of one or more fields, separated by commas. The use of the comma as a field separator is the source of the name for this file format. The CSV file format is not standardized. The basic idea of separating fields with a comma is clear, but that idea gets complicated when the field data may also contain commas or even embedded line-breaks. CSV implementations may not handle such field data, or they may use quotation marks to surround the field. Quotation does not solve everything: some fields may need embedded quotation marks, so a CSV implementation may include escape characters or escape sequences.

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Is your CAPTCHA Strong enough !!

We have seen a lot of DoS (Denial of Service) attacks in recent times. An old but promising solution to DoS attacks in web applications is to have CAPTCHA implemented in the publicly available form/pages.  However, all CAPTCHA implementations are not quite safe, and some implementations would give the user a headache.

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There are recent developments on simplifying CAPTCHA- But on simplifying, some developers forget the purpose of CAPTCHA.
Well, what is the purpose of using CAPTCHA?

In simple words CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) is a program to 'ensure' that the user is a human.

Almost 80% of custom CAPTCHA implementations are found to be unsafe during our evaluations. So what all are the measures to make sure the application has safe and simple CAPTCHA?

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Understanding and Testing Web Services – Part 1

V1sXtMost of the time folks find it really difficult to test web services. It is because we don't have proper knowledge of web services. Before any testing it is important to understand the system, we should know what can be the positive and negative sides of the technology and implementations of that application. Lets dive into the depth of web service testing. To provide a better security solution to the web service we should  have a brief understanding of web services, their architectural styles, their constraints and their characteristics that are responsible for their strength as well as weakness.

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No CAPTCHA reCAPTCHA

CAPTCHA-cartoonHow many times you feel affronted while reading those stupid numbers or words and re-entering it just to prove that you are a human. We call them CAPTCHA(Completely Automated Public Turing test to tell Computers and Humans Apart) and recommend it to avoid several kind of flooding attacks, brute force attacks and sometimes even for CSRF attacks.
It's time-consuming as well as frustrating.

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SQL Injection- Not a Cup of Cake

What is SQL Injection:

I have gone through many SQL Injectioimagesn tutorials before writing this post. One thing was common at every place, the queries coming from the readers. Many people don’t know what actually SQL Injection is. They think that they can easily enter into the database and make some changes, or they can simply inject some query and will have the username and password of the administrator. Well !!! Till some extent the concept is true but it is not that much easy.

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