A vulnerability classified as critical was found in TOTOLINK CP900 6.3c.566. This vulnerability affects the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument File leads to buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-273556. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.