Avahi 0.8 allows a local denial of service (NULL pointer dereference and daemon crash) against avahi-daemon via the D-Bus interface or a "ping .local" command.
The MITRE CVE dictionary describes this issue as:
Avahi 0.8 allows a local denial of service (NULL pointer dereference and daemon crash) against avahi-daemon via the D-Bus interface or a "ping .local" command.