RHSA-2011:0779: Moderate: avahi security and bug fix update

Avahi is an implementation of the DNS Service Discovery and Multicast DNSspecifications for Zero Configuration Networking. It facilitates servicediscovery on a local network. Avahi and Avahi-aware applications allow youto plug your computer into a network and, with no configuration, view otherpeople to chat with, view printers to print to, and find shared files onother computers.A flaw was found in the way the Avahi daemon (avahi-daemon) processedMulticast DNS (mDNS) packets with an empty payload. An attacker on thelocal network could use this flaw to cause avahi-daemon on a target systemto enter an infinite loop via an empty mDNS UDP packet. (CVE-2011-1002)This update also fixes the following bug: Previously, the avahi packages in Red Hat Enterprise Linux 6 were not compiled with standard RPM CFLAGS; therefore, the Stack Protector andFortify Source protections were not enabled, and the debuginfo packages didnot contain the information required for debugging. This update correctsthis issue by using proper CFLAGS when compiling the packages. (BZ#629954,BZ#684276)All users are advised to upgrade to these updated packages, which contain abackported patch to correct these issues. After installing the update,avahi-daemon will be restarted automatically.