CVE-2019-10166

It was discovered that libvirtd would permit readonly clients to use the virDomainManagedSaveDefineXML() API, which would permit them to modify managed save state files. If a managed save had already been created by a privileged user, a local attacker could modify this file such that libvirtd would execute an arbitrary program when the domain was resumed.

• This vulnerability requires access to the libvirt socket, normally in /var/run/libvirt/libvirt_sock_ro. Typically in hypervisor environments, local user accounts are not supported so no untrusted users should be able to access this socket.
• Red Hat Gluster Storage 3 is not affected by this vulnerability as libvirtd daemon is not shipped in Gluster.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

The Unix permissions of libvirt's read-only socket can be made more restrictive than the default (0777) by editing /etc/libvirt/libvirtd.conf. The settings unix_sock_group = libvirt and unix_sock_ro_perms = 0770 will restrict access to only members of libvirt, who already have management access to virtual machines.