A double free memory issue was found to occur in the libvirt API responsible for requesting information about network interfaces of a running QEMU domain. This flaw affects the polkit access control driver. Specifically, clients connecting to the read-write socket with limited ACL permissions could use this flaw to crash the libvirt daemon, resulting in a denial of service, or potentially escalate their privileges on the system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability (CVE-2020-25637).