The Session Initiation Protocol (SIP) implementation in Columbia SIP User Agent (sipc) 1.74 and other versions before sipc 2.0 build 2003-02-21 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
http://www.cs.columbia.edu/~xiaotaow/sipc/ouspg.html