CVE 2017-7471

Quick Emulator (Qemu) built with the VirtFS, host directory sharing via Plan 9 File System (9pfs) support, is vulnerable to an improper access control issue. It could occur while accessing files on a shared host directory. A privileged user inside guest could use this flaw to access host file system beyond the shared folder and potentially escalating their privileges on a host.

See the CVE page on Mitre.org for more details.