Xen 3.3.x through 4.5.x enables logging for PCI MSI-X pass-through error messages, which allows local x86 HVM guests to cause a denial of service (host disk consumption) via certain invalid operations.
Exploitability
AV:LAC:LAu:NImpact
C:NI:NA:C4.9/AV:L/AC:L/Au:N/C:N/I:N/A:C