This vulnerability allows network-adjacent attackers to disclose sensitive information on affected installations of D-Link DAP-2020 1.01rc001 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of the getpage parameter provided to the webproc endpoint. The issue results from the lack of proper validation of a user-supplied path prior to using it in file operations. An attacker can leverage this vulnerability to disclose information in the context of root. Was ZDI-CAN-12103.
https://www.zerodayinitiative.com/advisories/ZDI-21-976/
https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10201