Qemu before version 2.9 is vulnerable to an improper link following when built with the VirtFS. 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.
http://www.openwall.com/lists/oss-security/2017/01/17/12
http://www.securityfocus.com/bid/95461
http://www.securitytracker.com/id/1037604
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-9602
https://lists.debian.org/debian-lts-announce/2018/09/msg00007.html
https://lists.gnu.org/archive/html/qemu-devel/2017-01/msg06225.html
https://lists.gnu.org/archive/html/qemu-devel/2017-02/msg04347.html
Source: MITRE
Published: 2018-04-26
Updated: 2019-10-09
Type: CWE-59
Base Score: 9
Vector: AV:N/AC:L/Au:S/C:C/I:C/A:C
Impact Score: 10
Exploitability Score: 8
Severity: HIGH
Base Score: 8.8
Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Impact Score: 5.9
Exploitability Score: 2.8
Severity: HIGH