Total
443 CVE
| CVE | Vendors | Products | Updated | CVSS v2 | CVSS v3 |
|---|---|---|---|---|---|
| CVE-2021-28696 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-09-28 | 4.6 MEDIUM | 6.8 MEDIUM |
| IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Both AMD and Intel allow ACPI tables to specify regions of memory which should be left untranslated, which typically means these addresses should pass the translation phase unaltered. While these are typically device specific ACPI properties, they can also be specified to apply to a range of devices, or even all devices. On all systems with such regions Xen failed to prevent guests from undoing/replacing such mappings (CVE-2021-28694). On AMD systems, where a discontinuous range is specified by firmware, the supposedly-excluded middle range will also be identity-mapped (CVE-2021-28695). Further, on AMD systems, upon de-assigment of a physical device from a guest, the identity mappings would be left in place, allowing a guest continued access to ranges of memory which it shouldn't have access to anymore (CVE-2021-28696). | |||||
| CVE-2021-28698 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-09-28 | 4.9 MEDIUM | 5.5 MEDIUM |
| long running loops in grant table handling In order to properly monitor resource use, Xen maintains information on the grant mappings a domain may create to map grants offered by other domains. In the process of carrying out certain actions, Xen would iterate over all such entries, including ones which aren't in use anymore and some which may have been created but never used. If the number of entries for a given domain is large enough, this iterating of the entire table may tie up a CPU for too long, starving other domains or causing issues in the hypervisor itself. Note that a domain may map its own grants, i.e. there is no need for multiple domains to be involved here. A pair of "cooperating" guests may, however, cause the effects to be more severe. | |||||
| CVE-2021-28697 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-09-28 | 4.6 MEDIUM | 7.8 HIGH |
| grant table v2 status pages may remain accessible after de-allocation Guest get permitted access to certain Xen-owned pages of memory. The majority of such pages remain allocated / associated with a guest for its entire lifetime. Grant table v2 status pages, however, get de-allocated when a guest switched (back) from v2 to v1. The freeing of such pages requires that the hypervisor know where in the guest these pages were mapped. The hypervisor tracks only one use within guest space, but racing requests from the guest to insert mappings of these pages may result in any of them to become mapped in multiple locations. Upon switching back from v2 to v1, the guest would then retain access to a page that was freed and perhaps re-used for other purposes. | |||||
| CVE-2021-28695 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-09-28 | 4.6 MEDIUM | 6.8 MEDIUM |
| IOMMU page mapping issues on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Both AMD and Intel allow ACPI tables to specify regions of memory which should be left untranslated, which typically means these addresses should pass the translation phase unaltered. While these are typically device specific ACPI properties, they can also be specified to apply to a range of devices, or even all devices. On all systems with such regions Xen failed to prevent guests from undoing/replacing such mappings (CVE-2021-28694). On AMD systems, where a discontinuous range is specified by firmware, the supposedly-excluded middle range will also be identity-mapped (CVE-2021-28695). Further, on AMD systems, upon de-assigment of a physical device from a guest, the identity mappings would be left in place, allowing a guest continued access to ranges of memory which it shouldn't have access to anymore (CVE-2021-28696). | |||||
| CVE-2022-26363 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-24 | 7.2 HIGH | 6.7 MEDIUM |
| x86 pv: Insufficient care with non-coherent mappings T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, Xen's safety logic doesn't account for CPU-induced cache non-coherency; cases where the CPU can cause the content of the cache to be different to the content in main memory. In such cases, Xen's safety logic can incorrectly conclude that the contents of a page is safe. | |||||
| CVE-2022-26362 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-24 | 6.9 MEDIUM | 6.4 MEDIUM |
| x86 pv: Race condition in typeref acquisition Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, the logic for acquiring a type reference has a race condition, whereby a safely TLB flush is issued too early and creates a window where the guest can re-establish the read/write mapping before writeability is prohibited. | |||||
| CVE-2022-26364 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-24 | 7.2 HIGH | 6.7 MEDIUM |
| x86 pv: Insufficient care with non-coherent mappings T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen maintains a type reference count for pages, in addition to a regular reference count. This scheme is used to maintain invariants required for Xen's safety, e.g. PV guests may not have direct writeable access to pagetables; updates need auditing by Xen. Unfortunately, Xen's safety logic doesn't account for CPU-induced cache non-coherency; cases where the CPU can cause the content of the cache to be different to the content in main memory. In such cases, Xen's safety logic can incorrectly conclude that the contents of a page is safe. | |||||
| CVE-2022-21123 | 5 Debian, Fedoraproject, Intel and 2 more | 7 Debian Linux, Fedora, Sgx Dcap and 4 more | 2022-08-19 | 2.1 LOW | 5.5 MEDIUM |
| Incomplete cleanup of multi-core shared buffers for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access. | |||||
| CVE-2022-21125 | 5 Debian, Fedoraproject, Intel and 2 more | 7 Debian Linux, Fedora, Sgx Dcap and 4 more | 2022-08-19 | 2.1 LOW | 5.5 MEDIUM |
| Incomplete cleanup of microarchitectural fill buffers on some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access. | |||||
| CVE-2022-21166 | 5 Debian, Fedoraproject, Intel and 2 more | 7 Debian Linux, Fedora, Sgx Dcap and 4 more | 2022-08-19 | 2.1 LOW | 5.5 MEDIUM |
| Incomplete cleanup in specific special register write operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access. | |||||
| CVE-2022-23033 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-19 | 4.6 MEDIUM | 7.8 HIGH |
| arm: guest_physmap_remove_page not removing the p2m mappings The functions to remove one or more entries from a guest p2m pagetable on Arm (p2m_remove_mapping, guest_physmap_remove_page, and p2m_set_entry with mfn set to INVALID_MFN) do not actually clear the pagetable entry if the entry doesn't have the valid bit set. It is possible to have a valid pagetable entry without the valid bit set when a guest operating system uses set/way cache maintenance instructions. For instance, a guest issuing a set/way cache maintenance instruction, then calling the XENMEM_decrease_reservation hypercall to give back memory pages to Xen, might be able to retain access to those pages even after Xen started reusing them for other purposes. | |||||
| CVE-2022-23034 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-19 | 2.1 LOW | 5.5 MEDIUM |
| A PV guest could DoS Xen while unmapping a grant To address XSA-380, reference counting was introduced for grant mappings for the case where a PV guest would have the IOMMU enabled. PV guests can request two forms of mappings. When both are in use for any individual mapping, unmapping of such a mapping can be requested in two steps. The reference count for such a mapping would then mistakenly be decremented twice. Underflow of the counters gets detected, resulting in the triggering of a hypervisor bug check. | |||||
| CVE-2022-23035 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-19 | 4.7 MEDIUM | 4.6 MEDIUM |
| Insufficient cleanup of passed-through device IRQs The management of IRQs associated with physical devices exposed to x86 HVM guests involves an iterative operation in particular when cleaning up after the guest's use of the device. In the case where an interrupt is not quiescent yet at the time this cleanup gets invoked, the cleanup attempt may be scheduled to be retried. When multiple interrupts are involved, this scheduling of a retry may get erroneously skipped. At the same time pointers may get cleared (resulting in a de-reference of NULL) and freed (resulting in a use-after-free), while other code would continue to assume them to be valid. | |||||
| CVE-2021-28710 | 2 Fedoraproject, Xen | 2 Fedora, Xen | 2022-08-15 | 6.9 MEDIUM | 8.8 HIGH |
| certain VT-d IOMMUs may not work in shared page table mode For efficiency reasons, address translation control structures (page tables) may (and, on suitable hardware, by default will) be shared between CPUs, for second-level translation (EPT), and IOMMUs. These page tables are presently set up to always be 4 levels deep. However, an IOMMU may require the use of just 3 page table levels. In such a configuration the lop level table needs to be stripped before inserting the root table's address into the hardware pagetable base register. When sharing page tables, Xen erroneously skipped this stripping. Consequently, the guest is able to write to leaf page table entries. | |||||
| CVE-2021-28702 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-08-15 | 4.6 MEDIUM | 7.6 HIGH |
| PCI devices with RMRRs not deassigned correctly Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR"). These are typically used for platform tasks such as legacy USB emulation. If such a device is passed through to a guest, then on guest shutdown the device is not properly deassigned. The IOMMU configuration for these devices which are not properly deassigned ends up pointing to a freed data structure, including the IO Pagetables. Subsequent DMA or interrupts from the device will have unpredictable behaviour, ranging from IOMMU faults to memory corruption. | |||||
| CVE-2021-26313 | 6 Amd, Arm, Broadcom and 3 more | 11 Ryzen 5 5600x, Ryzen 7 2700x, Ryzen Threadripper 2990wx and 8 more | 2022-08-01 | 2.1 LOW | 5.5 MEDIUM |
| Potential speculative code store bypass in all supported CPU products, in conjunction with software vulnerabilities relating to speculative execution of overwritten instructions, may cause an incorrect speculation and could result in data leakage. | |||||
| CVE-2022-26356 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-07-29 | 4.0 MEDIUM | 5.6 MEDIUM |
| Racy interactions between dirty vram tracking and paging log dirty hypercalls Activation of log dirty mode done by XEN_DMOP_track_dirty_vram (was named HVMOP_track_dirty_vram before Xen 4.9) is racy with ongoing log dirty hypercalls. A suitably timed call to XEN_DMOP_track_dirty_vram can enable log dirty while another CPU is still in the process of tearing down the structures related to a previously enabled log dirty mode (XEN_DOMCTL_SHADOW_OP_OFF). This is due to lack of mutually exclusive locking between both operations and can lead to entries being added in already freed slots, resulting in a memory leak. | |||||
| CVE-2022-26358 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-07-29 | 4.4 MEDIUM | 7.8 HIGH |
| IOMMU: RMRR (VT-d) and unity map (AMD-Vi) handling issues T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR") for Intel VT-d or Unity Mapping ranges for AMD-Vi. These are typically used for platform tasks such as legacy USB emulation. Since the precise purpose of these regions is unknown, once a device associated with such a region is active, the mappings of these regions need to remain continuouly accessible by the device. This requirement has been violated. Subsequent DMA or interrupts from the device may have unpredictable behaviour, ranging from IOMMU faults to memory corruption. | |||||
| CVE-2022-26359 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2022-07-29 | 4.4 MEDIUM | 7.8 HIGH |
| IOMMU: RMRR (VT-d) and unity map (AMD-Vi) handling issues T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Certain PCI devices in a system might be assigned Reserved Memory Regions (specified via Reserved Memory Region Reporting, "RMRR") for Intel VT-d or Unity Mapping ranges for AMD-Vi. These are typically used for platform tasks such as legacy USB emulation. Since the precise purpose of these regions is unknown, once a device associated with such a region is active, the mappings of these regions need to remain continuouly accessible by the device. This requirement has been violated. Subsequent DMA or interrupts from the device may have unpredictable behaviour, ranging from IOMMU faults to memory corruption. | |||||
| CVE-2020-15566 | 2 Debian, Xen | 2 Debian Linux, Xen | 2022-07-12 | 4.7 MEDIUM | 6.5 MEDIUM |
| An issue was discovered in Xen through 4.13.x, allowing guest OS users to cause a host OS crash because of incorrect error handling in event-channel port allocation. The allocation of an event-channel port may fail for multiple reasons: (1) port is already in use, (2) the memory allocation failed, or (3) the port we try to allocate is higher than what is supported by the ABI (e.g., 2L or FIFO) used by the guest or the limit set by an administrator (max_event_channels in xl cfg). Due to the missing error checks, only (1) will be considered an error. All the other cases will provide a valid port and will result in a crash when trying to access the event channel. When the administrator configured a guest to allow more than 1023 event channels, that guest may be able to crash the host. When Xen is out-of-memory, allocation of new event channels will result in crashing the host rather than reporting an error. Xen versions 4.10 and later are affected. All architectures are affected. The default configuration, when guests are created with xl/libxl, is not vulnerable, because of the default event-channel limit. | |||||