OTP Bypass Really is it possible! How To Bypass OTP Burp suite

Yes. So welcome guys. Today we are going to see  authentication bypass vulnerability. So what is authentication bypass? Why are we going to do authentication bypass? What is the severity of this attack and what are the different  ways to do account takeovers? Basically all this will be  achieved in further slides. So let's see how odd bypass works. As we can see on the client end, at  the left side and at the right side, at the server end, when  the client is communicating with the server and sending one request  to the server, the server will respond. To the request by sending a response  and when the client is able to modify the response let's say instead of client  attacker is able to modify the response then there becomes authentication  bypass if the application is just checking the client side code  instead of checking the server side code. So we are going to see authentication bypass in which we will see OTP  bypass one time passwords bypass. So basically checking whether the OTPs are right or wrong improperly  leads to this type of bypass. Verifying at the client side only and  taking decisions is very dangerous. Only allowing logging into the application based on true or false conditions  are also very dangerous. So it's practical time. And let's see one of the OTP bypass vulnerability under authentication bypass attack. As you can see there is an application called as Healthy In on which  I am just making an account. I am signing up using my details in which I have entered, my name, my email  address, my mobile number and a password. And now I'm going to hit sign  up after clicking on sign up. As you can see, the application  has sent an OTP to my number. So let me just enter the OTP as any random four digits and the application  will tell me it is an incorrect OTP. Obviously guys, because this is a wrong OTP that I have entered into the application. Now what I will do, I will go in my burp suit and I  will again enter the wrong OTP. As you can see guys, this is the request  which is going to the API of Healthy M. This is an API call request  which is going to the web server. As in the API request. You can see this is a post-type type f request and the body contains the mobile number the OTP. So I will forward   this request now. And before forwarding I did response. I want to see the response of this request. So I did intercept the response. Now I will forward this request and as I did intercept response to this request  option, I am able to see the response of this API request that was sent  and in the response guys, you can see in the body it is saying status  zero message incorrect OTP. Please try again. As we already saw onto the website, the OTP is wrong and there comes an  error message which says incorrect OTP. Please try again. So now what we are going to do is we are going to modify the status as one and we  are going to write in the message correct OTP and forward this response to our browser. And let's wait for the browser and the browser will get automatically refreshed. The application has now logged  me in into my healthy account. As you can see, I cannot change the number, the  email and I'm inside the application. So through this way I was able to  perform a valid authentication bypass. So basically a OTP bypass into a healthy N  application wherein I achieved this attack by doing the response manipulation  as the application was vulnerable, as the application was only  checking at the client side code. Thank you. Thank you.