The ippReadIO function in cups/ipp.c in cupsd in CUPS before 1.3.10 does not properly initialize memory for IPP request packets, which allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a scheduler request with two consecutive IPP_TAG_UNSUPPORTED tags.
https://exchange.xforce.ibmcloud.com/vulnerabilities/50926
https://bugzilla.redhat.com/show_bug.cgi?id=500972
http://www.ubuntu.com/usn/USN-780-1
http://support.apple.com/kb/HT3865
http://lists.opensuse.org/opensuse-security-announce/2009-07/msg00002.html
http://lists.apple.com/archives/security-announce/2009/Sep/msg00004.html