The (1) XENMEM_decrease_reservation, (2) XENMEM_populate_physmap, and (3) XENMEM_exchange hypercalls in Xen 4.2 and earlier allow local guest administrators to cause a denial of service (long loop and hang) via a crafted extent_order value.

Stack-based buffer overflow in the dirty video RAM tracking functionality in Xen 3.4 through 4.1 allows local HVM guest OS administrators to cause a denial of service (crash) via a large bitmap image.

Xen 3.4 through 4.2, and possibly earlier versions, does not properly synchronize the p2m and m2p tables when the set_p2m_entry function fails, which allows local HVM guest OS administrators to cause a denial of service (memory consumption and assertion failure), aka "Memory mapping failure DoS vulnerability."

Xen 3.4 through 4.2, and possibly earlier versions, allows local guest OS administrators to cause a denial of service (Xen infinite loop and physical CPU consumption) by setting a VCPU with an "inappropriate deadline."