Уязвимость гипервизора Xen, связанная с ошибками сопоставления прав доступа, позволяющая нарушителю повысить свои привилегии или вызвать отказ в обслуживании

Уязвимость функции alloc_heap_pages гипервизора Xen, позволяющая нарушителю выполнить произвольный код или вызвать отказ в обслуживании

Уязвимость гипервизора Xen, связанная с неконтролируемым расходом ресурсов, позволяющая нарушителю вызвать отказ в обслуживании или повысить свои привилегии

Уязвимость гипервизора Xen, связанная с недостатками разграничения доступа, позволяющая нарушителю вызвать отказ в обслуживании или повысить свои привилегии

Уязвимость гипервизора Xen, связаная с ошибками в процедуре копирования разрешений, позволяющая нарушителю вызвать отказ в обслуживании, повысить свои привилегии или раскрыть защищаемую инфоррмацию

Уязвимость гипервизора Xen, связанная с использованием памяти после её освобождения, позволяющая нарушителю получить конфиденциальную информацию, повысить свои привилегии или вызвать аварийное завершение работы приложения

A parameter verification issue was discovered in Xen through 4.9.x. The function `alloc_heap_pages` allows callers to specify the first NUMA node that should be used for allocations through the `memflags` parameter; the node is extracted using the `MEMF_get_node` macro. While the function checks to see if the special constant `NUMA_NO_NODE` is specified, it otherwise does not handle the case where `node >= MAX_NUMNODES`. This allows an out-of-bounds access to an internal array.

A domain cleanup issue was discovered in the C xenstore daemon (aka cxenstored) in Xen through 4.9.x. When shutting down a VM with a stubdomain, a race in cxenstored may cause a double-free. The xenstored daemon may crash, resulting in a DoS of any parts of the system relying on it (including domain creation / destruction, ballooning, device changes, etc.).

A grant unmapping issue was discovered in Xen through 4.9.x. When removing or replacing a grant mapping, the x86 PV specific path needs to make sure page table entries remain in sync with other accounting done. Although the identity of the page frame was validated correctly, neither the presence of the mapping nor page writability were taken into account.

An issue was discovered in Xen through 4.9.x allowing x86 HVM guest OS users to cause a denial of service (hypervisor crash) or possibly gain privileges because self-linear shadow mappings are mishandled for translated guests.

An issue was discovered in Xen through 4.9.x allowing x86 PV guest OS users to cause a denial of service (memory leak) because reference counts are mishandled.

An issue was discovered in Xen through 4.9.x allowing x86 SVM PV guest OS users to cause a denial of service (hypervisor crash) or gain privileges because IDT settings are mishandled during CPU hotplugging.

An issue was discovered in Xen through 4.9.x allowing x86 PV guest OS users to cause a denial of service (unbounded recursion, stack consumption, and hypervisor crash) or possibly gain privileges via crafted page-table stacking.

An issue was discovered in Xen 4.4.x through 4.9.x allowing ARM guest OS users to cause a denial of service (prevent physical CPU usage) because of lock mishandling upon detection of an add-to-physmap error.

An issue was discovered in Xen through 4.9.x. Grant copying code made an implication that any grant pin would be accompanied by a suitable page reference. Other portions of code, however, did not match up with that assumption. When such a grant copy operation is being done on a grant of a dying domain, the assumption turns out wrong. A malicious guest administrator can cause hypervisor memory corruption, most likely resulting in host crash and a Denial of Service. Privilege escalation and information leaks cannot be ruled out.

An issue was discovered in Xen through 4.9.x allowing HVM guest OS users to cause a denial of service (infinite loop and host OS hang) by leveraging the mishandling of Populate on Demand (PoD) errors.

An issue was discovered in Xen through 4.9.x allowing HVM guest OS users to gain privileges on the host OS, obtain sensitive information, or cause a denial of service (BUG and host OS crash) by leveraging the mishandling of Populate on Demand (PoD) Physical-to-Machine (P2M) errors.

An issue was discovered in Xen through 4.9.x on the ARM platform allowing guest OS users to obtain sensitive information from DRAM after a reboot, because disjoint blocks, and physical addresses that do not start at zero, are mishandled.

An issue was discovered in Xen through 4.9.x allowing guest OS users to cause a denial of service (host OS crash) or gain host OS privileges by leveraging an incorrect mask for reference-count overflow checking in shadow mode.

An issue was discovered in Xen through 4.9.x allowing guest OS users to cause a denial of service (host OS crash) or gain host OS privileges by leveraging incorrect error handling for reference counting in shadow mode.

An issue was discovered in Xen through 4.9.x allowing PV guest OS users to cause a denial of service (host OS crash) if shadow mode and log-dirty mode are in place, because of an incorrect assertion related to M2P.

An issue was discovered in Xen through 4.9.x allowing PV guest OS users to cause a denial of service (host OS crash) or gain host OS privileges in shadow mode by mapping a certain auxiliary page.