The System.CodeDom.Compiler classes in Novell Mono create temporary files with insecure permissions, which allows local users to overwrite arbitrary files or execute arbitrary code via a symlink attack.
https://exchange.xforce.ibmcloud.com/vulnerabilities/29353
http://www.vupen.com/english/advisories/2006/3911
http://www.ubuntu.com/usn/usn-357-1
http://www.securityfocus.com/bid/20340
http://www.novell.com/linux/security/advisories/2006_73_mono.html
http://www.mandriva.com/security/advisories?name=MDKSA-2006:188
http://security.gentoo.org/glsa/glsa-200611-23.xml
http://secunia.com/advisories/23776
http://secunia.com/advisories/23213
http://secunia.com/advisories/23154
http://secunia.com/advisories/22614
http://secunia.com/advisories/22277