I am trying to better understand and determine the impact and implications of a web app where data tamping is possible.
When discussing data tampering, I am referring to when you are able to use a tool such as BurpSuite or Tamper Data to intercept a request and modify the data and submit it successfully.
I understand that this will allow an attacker to evade Client-side validations. For example, if the client does not allow certain symbols e.g. (!#) etc, an attack can input the correct details which the client will validate and then intercept the request and modify the data to include those symbols. But I'm thinking there is more than just the evasion of client-side validation that this vulnerability allows.
I am also thinking it perhaps opens the door to allow Dictionary-attacks using BurpSuite or Brute-force logins to user accounts since data can be intercepted and modified which can be used to test username and password combinations.
Would appreciate any insight regarding the implications of a Data Tampering vulnerability.