The xenDaemonListDefinedDomains function in xen/xend_internal.c in libvirt 1.1.1 allows remote authenticated users to cause a denial of service (memory corruption and crash) via vectors involving the virConnectListDefinedDomains API function.
http://libvirt.org/git/?p=libvirt.git%3Ba=commitdiff%3Bh=0e671a16