Waching daily Dec 29 2017

Hey Everyone I am Vikram Salunke

and welcome to the Web Application Penetration Testing

and Secure Coding In the last video

we analyzed HTTP Request sent by the web browser to the web server

now in this video we will analyze

response coming back from web server to web browser

so, let's get started we are in our Kali machine once again

in the location bar type vulnerable.app

it is saying connecting that means our request is currently in the

Burp we will go the Burp

Request is going to vulnerable.app these are the request headers

which we saw in a last video we will click on Forward

and now request has reached to the web server and web server has sent

the response back this is a response back from the web server

and these are some new HTTP Response headers

and now let's analyze those now let's look at our connection once again

this is our Firefox web browser this is vulnerable.app web server

and we have configured burp proxy to listen to our connection

when we type vulnerable.app in the web browser

the request goes to Burp first after that when we click on Forward

the request will go to the web server and then web server will send response

and it will come to Burp proxy first

after that when we click on the Forward

that response will go to the Web Browser

in the last video we saw HTTP Request headers

now in this video we will see HTTP Response headers

coming back from web server to the web browser

let's look at Format of HTTP Message once again

first there are Headers after that there is blank line

and after that message body and this remains same for the

HTTP Request as well as for HTTP Response this is the HTTP Request header

which we saw in the last video and for that Request

web server sent the HTTP Response let's analyze the HTTP Response

first there is HTTP/1.1 200 OK

after that Date then Server

then Vary after that Content-Length

after that Connection: close and then Content-Type

and after that Actual Page Content

now let's analyze this HTTP Response

line by line first there is HTTP/1.1 200 OK

as we saw in the last video

the browser was communicating on HTTP/1.1 version

and same has been sent by the web server

after that there is 200 OK 200 is a Status Code

OK is that Status Code's meaning 200 OK status code means

the request has been successful

such as the Status codes

starts with 1xx are the information ones

the status codes which starts with 2xx

are success ones and in this case

we saw 200 OK the Status code

which starts with 3xx are Redirectional ones

and most common is 301 Moved Permanently

the status codes which starts with

4xx are known as Client Error and most common is

404 Not Found so, if the Resource is not available

to that web server then it sends Status Code

404 Not Found the Status Codes

which starts with 5xx are known as the

Server Error and most common is

500 Internal Server Error Now each of these Status codes

we will look in the detail in upcoming videos

next HTTP Response is Date

that means it is Date and Time of message created

next HTTP Response is Server the value for this

HTTP Response is Apache/2.4.29 (Debian)

that means it is web server banner different different

web server has different different banners in this case

the web server is Apache

that's why this Banner if there is some different

web server then banner will be different

next is as Accept-Encoding and as we saw

in the last video the Encoding information

was sent by the browser and this Response is generated

based on the Accept-Encoding next is Content-Length

this length is a message body length in bytes

next is a Connection: close that means we are closing this

connection and for the new request new

connection will be made next is a Content-Type

it is telling about the type of message body in this case

the type for message body is html at some cases it might be

some other format such as PDF etc.

now in this case these are the HTTP Response headers

after that there was a empty line and this is the actual message body of a

HTTP Response and this is actual content

which we see in a Web Browseer ok so, this is our

HTTP Response which we got from the server

HTTP/1.1 then Date

Server Content-Length

Connection etc. and there is

actual body of a message and when we click on Forward

this Response will go back to the Web Browser

click Forward and as we can see

the Response is back to the web browser That' what I had planned for this video

if you have any doubts, any questions then you can contact me on

following handles Thank you :)