Advantage Century Telecommunication (ACT) P202S IP Phone 1.01.21 running firmware 1.1.21 on VxWorks uses a hardcoded Network Time Protocol (NTP) server in Taiwan, which could allow remote attackers to provide false time information, block access to time information, or conduct other attacks.
https://exchange.xforce.ibmcloud.com/vulnerabilities/24149
http://www.securityfocus.com/bid/16288
http://secunia.com/advisories/18514
http://lists.grok.org.uk/pipermail/full-disclosure/2006-January/041434.html