A vulnerability was found in iteachyou Dreamer CMS up to 4.1.3. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the file /admin/attachment/download of the component Attachment Handler. The manipulation of the argument ID leads to improper authorization. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.