The Session Initiation Protocol (SIP) implementation in multiple dynamicsoft products including y and certain demo products for AppEngine allows remote attackers to cause a denial of service or execute arbitrary code via crafted INVITE messages, as demonstrated by the OUSPG PROTOS c07-sip test suite.
https://exchange.xforce.ibmcloud.com/vulnerabilities/11379
http://www.securityfocus.com/bid/6904
http://www.kb.cert.org/vuls/id/528719