An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are processing watch events using a single thread. If the events are received faster than the thread is able to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OO...
6.5CVSS
7.3AI Score
0.0004EPSS
An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped. However, the handler may not have time to run if the frontend quickly toggles between the ...
8.8CVSS
8.3AI Score
0.0004EPSS
An issue was discovered in Xen through 4.14.x. Recording of the per-vCPU control block mapping maintained by Xen and that of pointers into the control block is reversed. The consumer assumes, seeing the former initialized, that the latter are also ready for use. Malicious or buggy guest kernels can...
6.2CVSS
7AI Score
0.001EPSS
An issue was discovered in Xen through 4.14.x. A bounds check common to most operation time functions specific to FIFO event channels depends on the CPU observing consistent state. While the producer side uses appropriately ordered writes, the consumer side isn't protected against re-ordered reads,...
6.2CVSS
6.9AI Score
0.001EPSS
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.
5.5CVSS
6.4AI Score
0.001EPSS
Potential floating point value injection in all supported CPU products, in conjunction with software vulnerabilities relating to speculative execution with incorrect floating point results, may cause the use of incorrect data from FPVI and may result in data leakage.
5.5CVSS
6.4AI Score
0.001EPSS
An issue was discovered in Xen 4.9 through 4.14.x. On Arm, a guest is allowed to control whether memory accesses are bypassing the cache. This means that Xen needs to ensure that all writes (such as the ones during scrubbing) have reached the memory before handing over the page to a guest. Unfortun...
5.5CVSS
5.9AI Score
0.0004EPSS
An issue was discovered in Xen through 4.11.x, allowing x86 Intel HVM guest OS users to achieve unintended read/write DMA access, and possibly cause a denial of service (host OS crash) or gain privileges. This occurs because a backport missed a flush, and thus IOMMU updates were not always correct....
7.8CVSS
8.1AI Score
0.0004EPSS
An issue was discovered in the Linux kernel 5.9.x through 5.11.3, as used with Xen. In some less-common configurations, an x86 PV guest OS user can crash a Dom0 or driver domain via a large amount of I/O activity. The issue relates to misuse of guest physical addresses when a configuration has CONF...
6.5CVSS
5.9AI Score
0.0004EPSS
HVM soft-reset crashes toolstack libxl requires all data structures passed across its public interface to be initialized before use and disposed of afterwards by calling a specific set of functions. Many internal data structures also require this initialize / dispose discipline, but not all of them...
5.5CVSS
5.6AI Score
0.0004EPSS
x86: Speculative vulnerabilities with bare (non-shim) 32-bit PV guests 32-bit x86 PV guest kernels run in ring 1. At the time when Xen was developed, this area of the i386 architecture was rarely used, which is why Xen was able to use it to implement paravirtualisation, Xen's novel approach to virt...
5.5CVSS
6.7AI Score
0.0004EPSS
x86: TSX Async Abort protections not restored after S3 This issue relates to the TSX Async Abort speculative security vulnerability. Please see https://xenbits.xen.org/xsa/advisory-305.html for details. Mitigating TAA by disabling TSX (the default and preferred option) requires selecting a non-defa...
6.5CVSS
6.7AI Score
0.001EPSS
inappropriate x86 IOMMU timeout detection / handling IOMMUs process commands issued to them in parallel with the operation of the CPU(s) issuing such commands. In the current implementation in Xen, asynchronous notification of the completion of such commands is not used. Instead, the issuing CPU sp...
7.1CVSS
7.1AI Score
0.0004EPSS
xen/arm: Boot modules are not scrubbed The bootloader will load boot modules (e.g. kernel, initramfs...) in a temporary area before they are copied by Xen to each domain memory. To ensure sensitive data is not leaked from the modules, Xen must "scrub" them before handing the page over to the alloca...
5.5CVSS
6AI Score
0.0004EPSS
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 addresse...
6.8CVSS
6.8AI Score
0.002EPSS
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 addresse...
6.8CVSS
6.8AI Score
0.002EPSS
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 addresse...
6.8CVSS
6.8AI Score
0.002EPSS
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 s...
7.8CVSS
7.5AI Score
0.0004EPSS
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 w...
5.5CVSS
6.3AI Score
0.0004EPSS
inadequate grant-v2 status frames array bounds check The v2 grant table interface separates grant attributes from grant status. That is, when operating in this mode, a guest has two tables. As a result, guests also need to be able to retrieve the addresses that the new status tracking table can be ...
5.5CVSS
6.1AI Score
0.0004EPSS
xen/arm: No memory limit for dom0less domUs The dom0less feature allows an administrator to create multiple unprivileged domains directly from Xen. Unfortunately, the memory limit from them is not set. This allow a domain to allocate memory beyond what an administrator originally configured.
4.9CVSS
5.9AI Score
0.008EPSS
Another race in XENMAPSPACE_grant_table handling Guests are 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, are de-allocated when a guest switches (back) from ...
7.8CVSS
7.5AI Score
0.0004EPSS
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...
7.6CVSS
7.9AI Score
0.002EPSS
grant table v2 status pages may remain accessible after de-allocation (take two) 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 whe...
7CVSS
7AI Score
0.0004EPSS
PoD operations on misaligned GFNs T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assig...
8.8CVSS
8.5AI Score
0.001EPSS
issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have...
7.8CVSS
7.9AI Score
0.001EPSS
guests may exceed their designated memory limit When a guest is permitted to have close to 16TiB of memory, it may be able to issue hypercalls to increase its memory allocation beyond the administrator established limit. This is a result of a calculation done with 32-bit precision, which may overfl...
8.6CVSS
8.3AI Score
0.003EPSS
PoD operations on misaligned GFNs T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assig...
8.8CVSS
8.5AI Score
0.001EPSS
PoD operations on misaligned GFNs T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assig...
8.8CVSS
8.5AI Score
0.001EPSS
issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have...
7.8CVSS
7.9AI Score
0.001EPSS
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 ...
8.8CVSS
8.4AI Score
0.0004EPSS
Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as "drive...
6.5CVSS
6.9AI Score
0.001EPSS
Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as "drive...
6.5CVSS
6.9AI Score
0.001EPSS
Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as "drive...
6.5CVSS
6.9AI Score
0.001EPSS
An issue was discovered in Xen 4.12.3 through 4.12.4 and 4.13.1 through 4.14.x. An x86 HVM guest with PCI pass through devices can force the allocation of all IDT vectors on the system by rebooting itself with MSI or MSI-X capabilities enabled and entries setup. Such reboots will leak any vectors u...
5.5CVSS
5.5AI Score
0.0004EPSS
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.
5.5CVSS
6.3AI Score
0.0005EPSS
Incomplete cleanup of microarchitectural fill buffers on some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.
5.5CVSS
6.3AI Score
0.001EPSS
Incomplete cleanup in specific special register read operations for some Intel(R) Processors may allow an authenticated user to potentially enable information disclosure via local access.
5.5CVSS
6AI Score
0.0004EPSS
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.
5.5CVSS
6.3AI Score
0.0005EPSS
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 ha...
7.8CVSS
7.3AI Score
0.0004EPSS
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 map...
5.5CVSS
5.4AI Score
0.0004EPSS
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 th...
4.6CVSS
4.8AI Score
0.001EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backe...
7CVSS
7.3AI Score
0.0004EPSS
IBPB may not prevent return branch predictions from being specified by pre-IBPB branch targets leading to a potential information disclosure.
5.5CVSS
5.6AI Score
0.001EPSS