The emulation routines for unspecified X86 devices in Xen 3.2.x through 4.5.x does not properly initialize data, which allow local HVM guest users to obtain sensitive information via vectors involving an unsupported access size.
Exploitability
AV:LAC:LAu:NImpact
C:PI:NA:N2.1/AV:L/AC:L/Au:N/C:P/I:N/A:N