An issue was discovered in Xen through 4.9.x allowing HVM guest OS users to cause a denial of service (infinite loop and host OS hang) by leveraging the mishandling of Populate on Demand (PoD) errors.
https://xenbits.xen.org/xsa/advisory-246.html
https://support.citrix.com/article/CTX230138
https://security.gentoo.org/glsa/201801-14
https://lists.debian.org/debian-lts-announce/2018/10/msg00021.html
https://lists.debian.org/debian-lts-announce/2018/01/msg00003.html
http://www.securitytracker.com/id/1039878
http://www.securityfocus.com/bid/105954