OpenAM Reflected XSS in the OAuth2/OIDC `wap` consent page

Open Access Management (OpenAM) is an access management solution. From 13.0.0 until 16.1.2, the OAuth2 authorize endpoint's display=wap consent page reflects request-derived values through ConsentRequiredResource and wap/authorize.ftl without HTML escaping. An attacker can induce a user with an active OpenAM session to follow a crafted authorization link and execute JavaScript in the OpenAM origin, enabling session or cookie theft, CSRF-token disclosure, and actions with the victim's privileges. At least one registered OAuth2 client is required, but the attacker does not need to control that client. This issue is fixed in version 16.1.2.