Bojan Bogdanovic

Incorrectly configured access control security levels allow the caching of token permissions in a manner that enables them to be reused for another user's token sharing the same scopes. This can lead to a user gaining unauthorized permissions, including administrative access. Exploitation requires a more privileged user's token with identical scopes to be used first.

A flaw exists in Simple OAuth (OAuth2) & OpenID Connect that permits authentication bypass. This issue allows bypassing normal authentication mechanisms through an alternate path or channel.