Open redirect in https://www.rockstargames.com/GTAOnline/restricted-content/agegate/form may lead to Facebook OAuth token theft

Summary

In this report, the researcher identified an Open Redirect vulnerability in the age-gate code on the GTA Online sub-site. This vulnerability could also potentially have caused sensitive tokens to leak via the Referer header if it were exploited under specific circumstances. The Open Redirect was addressed and fixed thanks to the researcher's assistance.