Avahi before 0.6.15 does not verify the sender identity of netlink messages to ensure that they come from the kernel instead of another process, which allows local users to spoof network changes to Avahi.
https://tango.0pointer.de/pipermail/avahi-tickets/2006-November/000320.html
https://exchange.xforce.ibmcloud.com/vulnerabilities/30207
http://www.vupen.com/english/advisories/2006/4474
http://www.securityfocus.com/bid/21016
http://www.novell.com/linux/security/advisories/2006_26_sr.html
http://www.mandriva.com/security/advisories?name=MDKSA-2006:215
http://www.gentoo.org/security/en/glsa/glsa-200611-13.xml
http://securitytracker.com/id?1017257
http://secunia.com/advisories/23042
http://secunia.com/advisories/23020
http://secunia.com/advisories/22932
http://secunia.com/advisories/22852