A few weeks ago some colleagues from a development team told us about their worries on the JSON Web tokens (JWT) generation they were doing as part of a new tool integration they were working on. They had heard about several security issues regarding the use of JWT tokens so they asked us for help in order to validate if the tokens they were issuing were correct and met some basic security requirements.
We are currently working on a project to help automate security tests, APICheck, which we’ve recently released as open source. APICheck is comprised of a set of small tools that can be pipe chained in order to run several tests on API requests, so we got down to work with the development of a new tool for validating the JWT they were issuing, jwt-checker, in which we’ve implemented the ability to pass the validations on the tokens we’ll talk about. Below I’ll show you an example of a test implemented using the tool.