Secunia Security Advisory – A vulnerability has been reported in the ZTE ZXDSL 831 II Modem, which can be exploited by malicious people bypass certain security restrictions.
You can download this advisory from the following link: https://packetstormsecurity.com/files/download/80598/sa36348.txt
Source: https://packetstormsecurity.com/files/80598/Secunia-Security-Advisory-36348.html