Account takeover via attacker-controlled login parameters

Improper authentication in MacCMS 10.0 allows remote attackers to assume any user account through its public web login endpoint. The /index.php/user/login handler trusts attacker-controlled col and openid parameters, allowing col=user_id and a chosen identifier to replace password authentication. No prior account or user interaction is required; successful exploitation creates a session as the selected user and grants that account's privileges.