The create_pit_timer function in arch/x86/kvm/i8254.c in KVM 83, and possibly other versions, does not properly handle when Programmable Interval Timer (PIT) interrupt requests (IRQs) when a virtual interrupt controller (irqchip) is not available, which allows local users to cause a denial of service (NULL pointer dereference) by starting a timer.

QEMU-KVM, as used in the Hypervisor (aka rhev-hypervisor) in Red Hat Enterprise Virtualization (RHEV) 2.2 and KVM 83, does not properly validate guest QXL driver pointers, which allows guest OS users to cause a denial of service (invalid pointer dereference and guest OS crash) or possibly gain privileges via unspecified vectors.

The Hypervisor (aka rhev-hypervisor) in Red Hat Enterprise Virtualization (RHEV) 2.2, and KVM 83, when the Intel VT-x extension is enabled, allows guest OS users to cause a denial of service (NULL pointer dereference and host OS crash) via vectors related to instruction emulation.

The subpage MMIO initialization functionality in the subpage_register function in exec.c in QEMU-KVM, as used in the Hypervisor (aka rhev-hypervisor) in Red Hat Enterprise Virtualization (RHEV) 2.2 and KVM 83, does not properly select the index for access to the callback array, which allows guest OS users to cause a denial of service (guest OS crash) or possibly gain privileges via unspecified vectors.

The x86 emulator in KVM 83, when a guest is configured for Symmetric Multiprocessing (SMP), does not properly restrict writing of segment selectors to segment registers, which might allow guest OS users to cause a denial of service (guest OS crash) or gain privileges on the guest OS by leveraging access to a (1) IO port or (2) MMIO region, and replacing an instruction in between emulator entry and instruction fetch.

The x86 emulator in KVM 83, when a guest is configured for Symmetric Multiprocessing (SMP), does not use the Current Privilege Level (CPL) and I/O Privilege Level (IOPL) to restrict instruction execution, which allows guest OS users to cause a denial of service (guest OS crash) or gain privileges on the guest OS by leveraging access to a (1) IO port or (2) MMIO region, and replacing an instruction in between emulator entry and instruction fetch, a related issue to CVE-2010-0298.