And this lecture and the next few lectures we're going to talk about a vulnerability called Access has
access is short for a cross-site scripting this type of vulnerability allows an attacker to inject javascript
into a page so Javascript is a programming language and using this vulnerability an attacker would be
able to execute code written in javascript into a certain page into a website Javascript is a client
site language.
So when the code is executed it will be executed on the client on the user on the person who is browsing
the web page.
Its not going to be executed on the server.
So even if your code results into giving you a reverse shell the shell will be coming from the user
who is browsing the page and its not going to be coming from the Web site.
So any code you write in javascript will be exploited or will run on the target user on the people who
see the pages and its not on the web server so the web server is only going to be used as means of executing
the code or delivering the code.
There three main types of access as vulnerabilities is persistent or stored reflected and Home-Based
the stored access gets stored into the database.
So the code that you inject will be stored into the database or into the page so that every time any
person views that page your code will be executed.
And reflected one the code will only be executed when the target user runs a specific cure all crafted
or written by you.
So you'll be manipulating some sort of your L and send it to a target and when they run that target
when they run that.
The code will be executed
don't based results from javascript code written on the client.
So the code will actually be interpreted and run on the client side without having any communication
with the web server.
This could be very dangerous because sometimes web servers apply some sort of security infiltration
to check for access.
But with Home-Based the code never gets sent to the web server.
So the call will be interpreted and run on the web browser without even interacting with the web server
and these will be present into websites that update their content.
With that refresh so we've all used Web sites where you put your username for example and it loads in
straight away without having to check with the web server.
Or do you put some sort of a string and it doesn't search without communicating with the web server
or does something with communicating with a web server.
So if you're able to inject into that then this injection will not be validated.
So it will be executed straightaway and bypass all validations.