WordPressプラグイン「Membership & User Roles for WooCommerce (Automatic Role Changer)」に不適切な権限管理の脆弱性（CVE-2026-104767）

The Membership & User Roles for WooCommerce (Automatic Role Changer) plugin for WordPress is vulnerable to Privilege Escalation in versions up to, and including, 20260828. This is due to the `maybe_add_role_to_user()` function unconditionally re-assigning every role stored in the `dfxwcrc_foreign_roles` user meta cache without verifying that each cached role is still actively assigned by the external provider — a condition made permanent by `remember_foreign_roles()`, which merges new foreign roles into the cache but never evicts roles that have since been revoked. This makes it possible for authenticated attackers with subscriber-level access and above to restore a previously revoked Administrator role to their own account, gaining full administrative control of the site, by triggering any role-assignment event such as completing a purchase for a role-mapped product. Exploitation requires Replace Roles mode to be enabled and the attacker's account to have previously received Administrator legitimately through a separate role-management mechanism while the plugin was active, so that `administrator` was written into the `dfxwcrc_foreign_roles` user meta cache before the external provider revoked it.