GHSA-f66q-9rf6-8795: Flask-Security-Too: WebAuthn reauthentication freshness bypass via cross-user assertion

Flask-Security-Too 5.8.0 and 5.8.1 mark a session as reauthentication-fresh after processing a WebAuthn assertion whose proven credential belongs to a different user than the currently authenticated session user. The check that GHSA-97r5-pg8x-p63p added on the OAuth reauthentication path (user.email == current_user.email) is missing on the WebAuthn reauthentication path. An attacker who owns any WebAuthn credential registered to any account on the deployment can satisfy a victim session’s freshness gate by submitting their own WebAuthn proof into the victim session.