[Security] Report submitted — SubjectConfirmationData Recipient validation (private advisory) #1045

A potential security issue affecting SAML response validation has been reported
through the private security advisory process per SECURITY.md, rather than
here, in line with this project's disclosure policy.

Severity (preliminary): High
Advisory: GHSA-x37c-84ff-rv3g

No further detail is included in this public issue. Maintainers/incident-response
team have the full report.