Open Access Management (OpenAM) is an access management solution. In versions prior to 16.0.0, if the "claims_parameter_supported" parameter is activated, it is possible, thanks to the "oidc-claims-extension.groovy" script, to inject the value of one's choice into a claim contained in the id_token or in the user_info. In the request of an authorize function, a claims parameter containing a JSON file can be injected. This JSON file allows attackers to customize the claims returned by the "id_token" and "user_info" files. This allows for a very wide range of vulnerabilities depending on how clients use claims. For example, if some clients rely on an email field to identify a user, an attacker can choose the email address they want, and therefore assume any identity they choose. Version 16.0.0 fixes the issue.

Affected: Maven: org.openidentityplatform.openam:openam-oauth2

### Summary If the "claims_parameter_supported" parameter is activated, it is possible through the "oidc-claims-extension.groovy" script, to inject the value of choice into a claim contained in the id_token or in the user_info. Authorization function requests do not prevent a claims parameter containing a JSON file to be injected. This JSON file allows users to customize claims returned by the "id_token" and "user_info" files. This allows for a very wide range of vulnerabilities depending on how clients use claims. For example, if some clients rely on an email field to identify a user, users can choose to entera any email address, and therefore assume any chosen identity.