Posts

OAuth client credentials. How to find and utilize them for the bug bounty

OAuth client credentials grant type is a way how to OAuth application can authenticate itself.

Access to some admin endpoints with OAuth client credentials

The target is a fintech company that can centralize payments for companies and employees.

The diffskip tool for JS files

I monitor changes in target main scripts to find new features or juicy things like keys, tokens, or new endpoints. Because primarily it is black-box testing, the JS files are minified and contain much garbage in their diffs.

Access to all users data with OAuth client credentials

It is a real-world example of the OAuth client credentials attack vector.