Quick Emulator (Qemu) built with the USB redirector usb-guest support is vulnerable to a memory leakage flaw. It could occur while destroying the USB redirector in 'usbredir_handle_destroy'. A guest user/process could use this issue to leak host memory, resulting in DoS for a host.
https://security.gentoo.org/glsa/201701-49
https://lists.debian.org/debian-lts-announce/2018/09/msg00007.html
https://access.redhat.com/errata/RHSA-2017:2408
https://access.redhat.com/errata/RHSA-2017:2392