Multiple integer overflows in tools/libxc/xc_dom_bzimageloader.c in Xen 3.2, 3.3, 4.0, and 4.1 allow local users to cause a denial of service and possibly execute arbitrary code via a crafted paravirtualised guest kernel image that triggers (1) a buffer overflow during a decompression loop or (2) an out-of-bounds read in the loader involving unspecified length fields.

The fixup_page_fault function in arch/x86/traps.c in Xen 4.0.1 and earlier on 64-bit platforms, when paravirtualization is enabled, does not verify that kernel mode is used to call the handle_gdt_ldt_mapping_fault function, which allows guest OS users to cause a denial of service (host OS BUG_ON) via a crafted memory access.

The do_block_io_op function in (1) drivers/xen/blkback/blkback.c and (2) drivers/xen/blktap/blktap.c in Xen before 3.4.0 for the Linux kernel 2.6.18, and possibly other versions, allows guest OS users to cause a denial of service (infinite loop and CPU consumption) via a large production request index to the blkback or blktap back-end drivers. NOTE: some of these details are obtained from third party information.

The backend driver in Xen 3.x allows guest OS users to cause a denial of service via a kernel thread leak, which prevents the device and guest OS from being shut down or create a zombie domain, causes a hang in zenwatch, or prevents unspecified xm commands from working properly, related to (1) netback, (2) blkback, or (3) blktap.

The hypervisor_callback function in Xen, possibly before 3.4.0, as applied to the Linux kernel 2.6.30-rc4, 2.6.18, and probably other versions allows guest user applications to cause a denial of service (kernel oops) of the guest OS by triggering a segmentation fault in "certain address ranges."

qemu-dm.debug in Xen 3.2.1 allows local users to overwrite arbitrary files via a symlink attack on the /tmp/args temporary file.