The HVMOP_inject_msi function in Xen 4.2.x, 4.3.x, and 4.4.x does not properly check the return value from the IRQ setup check, which allows local HVM guest administrators to cause a denial of service (NULL pointer dereference and crash) via unspecified vectors. Per: http://cwe.mitre.org/data/definitions/476.html
"CWE-476: NULL Pointer Dereference"
Publication date: Tue, 30 Oct 2018 21:27:00 +0000