CVE-2026-12281 Shibboleth < 2.5.4 - Unauthenticated Administrator Account Creation via Identity Header Spoofing

The Shibboleth WordPress plugin before 2.5.4 does not fail closed when its HTTP header identity mode is enabled without an anti-spoofing key, treating any request that carries identity headers as an authenticated session without verifying them. On a deployment where untrusted client headers reach...