Rapid7 Vulnerability & Exploit Database

RHSA-2010:0528: avahi security update

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RHSA-2010:0528: avahi security 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 corrupted checksums. An attacker on thelocal network could use this flaw to cause avahi-daemon on a target systemto exit unexpectedly via specially-crafted mDNS packets. (CVE-2010-2244)A flaw was found in the way avahi-daemon processed incoming unicast mDNSmessages. If the mDNS reflector were enabled on a system, an attacker onthe local network could send a specially-crafted unicast mDNS message tothat system, resulting in its avahi-daemon flooding the network with amulticast packet storm, and consuming a large amount of CPU. Note: The mDNSreflector is disabled by default. (CVE-2009-0758)All users are advised to upgrade to these updated packages, which containbackported patches to correct these issues. After installing the update,avahi-daemon will be restarted automatically.


  • redhat-upgrade-avahi
  • redhat-upgrade-avahi-compat-howl
  • redhat-upgrade-avahi-compat-howl-devel
  • redhat-upgrade-avahi-compat-libdns_sd
  • redhat-upgrade-avahi-compat-libdns_sd-devel
  • redhat-upgrade-avahi-devel
  • redhat-upgrade-avahi-glib
  • redhat-upgrade-avahi-glib-devel
  • redhat-upgrade-avahi-qt3
  • redhat-upgrade-avahi-qt3-devel
  • redhat-upgrade-avahi-tools

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