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

Description

The OAuth2/OIDC consent page rendered for display=wap authorize requests reflected several request-derived values into the HTML response without escaping. An attacker who induces a user with an active OpenAM session to follow a crafted authorize link can execute arbitrary JavaScript in the OpenAM origin.

This is the same vulnerability class as CVE-2026-44203; that fix did not cover this code path.

Impact

Arbitrary JavaScript execution in the OpenAM origin in the victim's authenticated context — enabling session/cookie theft, CSRF-token exfiltration, and actions on behalf of the victim, up to administrative takeover if the victim is an administrator. Reachable on any deployment with at least one registered OAuth2 client; no attacker-controlled client and no special configuration required.

Mitigation

• Upgrade to 16.1.2 (or later).
• Until then, restrict/limit access to the OAuth2 authorize endpoint and treat unsolicited display=wap authorize links as untrusted.