n8n before 2.41.4 and 2.42.1 Credential Check Bypass via Agent Node Parameters

n8n before 2.41.4 and 2.42.0 before 2.42.1 does not validate credential ids stored in agent node parameters when an editor saves a shared workflow, because the check inspects only a node's credentials field. An editor can configure a Message an Agent node in inline mode with tools they control to resolve the owner's credentials and send decrypted secrets to an attacker-chosen destination.