Total
468 CVE
| CVE | Vendors | Products | Updated | CVSS v2 | CVSS v3 |
|---|---|---|---|---|---|
| CVE-2019-18425 | 4 Debian, Fedoraproject, Opensuse and 1 more | 4 Debian Linux, Fedora, Leap and 1 more | 2023-11-07 | 9.3 HIGH | 9.8 CRITICAL |
| An issue was discovered in Xen through 4.12.x allowing 32-bit PV guest OS users to gain guest OS privileges by installing and using descriptors. There is missing descriptor table limit checking in x86 PV emulation. When emulating certain PV guest operations, descriptor table accesses are performed by the emulating code. Such accesses should respect the guest specified limits, unless otherwise guaranteed to fail in such a case. Without this, emulation of 32-bit guest user mode calls through call gates would allow guest user mode to install and then use descriptors of their choice, as long as the guest kernel did not itself install an LDT. (Most OSes don't install any LDT by default). 32-bit PV guest user mode can elevate its privileges to that of the guest kernel. Xen versions from at least 3.2 onwards are affected. Only 32-bit PV guest user mode can leverage this vulnerability. HVM, PVH, as well as 64-bit PV guests cannot leverage this vulnerability. Arm systems are unaffected. | |||||
| CVE-2019-18422 | 3 Debian, Fedoraproject, Xen | 3 Debian Linux, Fedora, Xen | 2023-11-07 | 8.5 HIGH | 8.8 HIGH |
| An issue was discovered in Xen through 4.12.x allowing ARM guest OS users to cause a denial of service or gain privileges by leveraging the erroneous enabling of interrupts. Interrupts are unconditionally unmasked in exception handlers. When an exception occurs on an ARM system which is handled without changing processor level, some interrupts are unconditionally enabled during exception entry. So exceptions which occur when interrupts are masked will effectively unmask the interrupts. A malicious guest might contrive to arrange for critical Xen code to run with interrupts erroneously enabled. This could lead to data corruption, denial of service, or possibly even privilege escalation. However a precise attack technique has not been identified. | |||||
| CVE-2019-18421 | 4 Debian, Fedoraproject, Opensuse and 1 more | 4 Debian Linux, Fedora, Leap and 1 more | 2023-11-07 | 7.1 HIGH | 7.5 HIGH |
| An issue was discovered in Xen through 4.12.x allowing x86 PV guest OS users to gain host OS privileges by leveraging race conditions in pagetable promotion and demotion operations. There are issues with restartable PV type change operations. To avoid using shadow pagetables for PV guests, Xen exposes the actual hardware pagetables to the guest. In order to prevent the guest from modifying these page tables directly, Xen keeps track of how pages are used using a type system; pages must be "promoted" before being used as a pagetable, and "demoted" before being used for any other type. Xen also allows for "recursive" promotions: i.e., an operating system promoting a page to an L4 pagetable may end up causing pages to be promoted to L3s, which may in turn cause pages to be promoted to L2s, and so on. These operations may take an arbitrarily large amount of time, and so must be re-startable. Unfortunately, making recursive pagetable promotion and demotion operations restartable is incredibly complicated, and the code contains several races which, if triggered, can cause Xen to drop or retain extra type counts, potentially allowing guests to get write access to in-use pagetables. A malicious PV guest administrator may be able to escalate their privilege to that of the host. All x86 systems with untrusted PV guests are vulnerable. HVM and PVH guests cannot exercise this vulnerability. | |||||
| CVE-2019-18424 | 4 Debian, Fedoraproject, Opensuse and 1 more | 4 Debian Linux, Fedora, Leap and 1 more | 2023-11-07 | 6.9 MEDIUM | 6.8 MEDIUM |
| An issue was discovered in Xen through 4.12.x allowing attackers to gain host OS privileges via DMA in a situation where an untrusted domain has access to a physical device. This occurs because passed through PCI devices may corrupt host memory after deassignment. When a PCI device is assigned to an untrusted domain, it is possible for that domain to program the device to DMA to an arbitrary address. The IOMMU is used to protect the host from malicious DMA by making sure that the device addresses can only target memory assigned to the guest. However, when the guest domain is torn down, or the device is deassigned, the device is assigned back to dom0, thus allowing any in-flight DMA to potentially target critical host data. An untrusted domain with access to a physical device can DMA into host memory, leading to privilege escalation. Only systems where guests are given direct access to physical devices capable of DMA (PCI pass-through) are vulnerable. Systems which do not use PCI pass-through are not vulnerable. | |||||
| CVE-2018-19962 | 3 Citrix, Debian, Xen | 3 Xenserver, Debian Linux, Xen | 2023-11-07 | 6.9 MEDIUM | 7.8 HIGH |
| An issue was discovered in Xen through 4.11.x on AMD x86 platforms, possibly allowing guest OS users to gain host OS privileges because small IOMMU mappings are unsafely combined into larger ones. | |||||
| CVE-2018-19961 | 3 Citrix, Debian, Xen | 3 Xenserver, Debian Linux, Xen | 2023-11-07 | 6.9 MEDIUM | 7.8 HIGH |
| An issue was discovered in Xen through 4.11.x on AMD x86 platforms, possibly allowing guest OS users to gain host OS privileges because TLB flushes do not always occur after IOMMU mapping changes. | |||||
| CVE-2018-19965 | 3 Citrix, Debian, Xen | 3 Xenserver, Debian Linux, Xen | 2023-11-07 | 4.7 MEDIUM | 5.6 MEDIUM |
| An issue was discovered in Xen through 4.11.x allowing 64-bit PV guest OS users to cause a denial of service (host OS crash) because #GP[0] can occur after a non-canonical address is passed to the TLB flushing code. NOTE: this issue exists because of an incorrect CVE-2017-5754 (aka Meltdown) mitigation. | |||||
| CVE-2018-19966 | 2 Debian, Xen | 2 Debian Linux, Xen | 2023-11-07 | 7.2 HIGH | 8.8 HIGH |
| An issue was discovered in Xen through 4.11.x allowing x86 PV guest OS users to cause a denial of service (host OS crash) or possibly gain host OS privileges because of an interpretation conflict for a union data structure associated with shadow paging. NOTE: this issue exists because of an incorrect fix for CVE-2017-15595. | |||||
| CVE-2017-2620 | 5 Citrix, Debian, Qemu and 2 more | 10 Xenserver, Debian Linux, Qemu and 7 more | 2023-11-07 | 9.0 HIGH | 9.9 CRITICAL |
| Quick emulator (QEMU) before 2.8 built with the Cirrus CLGD 54xx VGA Emulator support is vulnerable to an out-of-bounds access issue. The issue could occur while copying VGA data in cirrus_bitblt_cputovideo. A privileged user inside guest could use this flaw to crash the QEMU process OR potentially execute arbitrary code on host with privileges of the QEMU process. | |||||
| CVE-2015-3456 | 3 Qemu, Redhat, Xen | 5 Qemu, Enterprise Linux, Enterprise Virtualization and 2 more | 2023-11-07 | 7.7 HIGH | N/A |
| The Floppy Disk Controller (FDC) in QEMU, as used in Xen 4.5.x and earlier and KVM, allows local guest users to cause a denial of service (out-of-bounds write and guest crash) or possibly execute arbitrary code via the (1) FD_CMD_READ_ID, (2) FD_CMD_DRIVE_SPECIFICATION_COMMAND, or other unspecified commands, aka VENOM. | |||||
| CVE-2015-2150 | 3 Linux, Ubuntu, Xen | 3 Linux Kernel, Ubuntu, Xen | 2023-11-07 | 4.9 MEDIUM | N/A |
| Xen 3.3.x through 4.5.x and the Linux kernel through 3.19.1 do not properly restrict access to PCI command registers, which might allow local guest OS users to cause a denial of service (non-maskable interrupt and host crash) by disabling the (1) memory or (2) I/O decoding for a PCI Express device and then accessing the device, which triggers an Unsupported Request (UR) response. | |||||
| CVE-2015-0777 | 2 Linux, Xen | 2 Linux Kernel, Xen | 2023-11-07 | 2.1 LOW | N/A |
| drivers/xen/usbback/usbback.c in linux-2.6.18-xen-3.4.0 (aka the Xen 3.4.x support patches for the Linux kernel 2.6.18), as used in the Linux kernel 2.6.x and 3.x in SUSE Linux distributions, allows guest OS users to obtain sensitive information from uninitialized locations in host OS kernel memory via unspecified vectors. | |||||
| CVE-2013-2076 | 1 Xen | 1 Xen | 2023-11-07 | 4.3 MEDIUM | N/A |
| Xen 4.0.x, 4.1.x, and 4.2.x, when running on AMD64 processors, only save/restore the FOP, FIP, and FDP x87 registers in FXSAVE/FXRSTOR when an exception is pending, which allows one domain to determine portions of the state of floating point instructions of other domains, which can be leveraged to obtain sensitive information such as cryptographic keys, a similar vulnerability to CVE-2006-1056. NOTE: this is the documented behavior of AMD64 processors, but it is inconsistent with Intel processors in a security-relevant fashion that was not addressed by the kernels. | |||||
| CVE-2012-4411 | 1 Xen | 1 Xen | 2023-11-07 | 4.6 MEDIUM | N/A |
| The graphical console in Xen 4.0, 4.1 and 4.2 allows local OS guest administrators to obtain sensitive host resource information via the qemu monitor. NOTE: this might be a duplicate of CVE-2007-0998. | |||||
| CVE-2011-3346 | 3 Qemu, Redhat, Xen | 3 Qemu, Enterprise Linux, Xen | 2023-11-07 | 4.0 MEDIUM | N/A |
| Buffer overflow in hw/scsi-disk.c in the SCSI subsystem in QEMU before 0.15.2, as used by Xen, might allow local guest users with permission to access the CD-ROM to cause a denial of service (guest crash) via a crafted SAI READ CAPACITY SCSI command. NOTE: this is only a vulnerability when root has manually modified certain permissions or ACLs. | |||||
| CVE-2015-8104 | 5 Canonical, Debian, Linux and 2 more | 6 Ubuntu Linux, Debian Linux, Linux Kernel and 3 more | 2023-10-10 | 4.7 MEDIUM | N/A |
| The KVM subsystem in the Linux kernel through 4.2.6, and Xen 4.3.x through 4.6.x, allows guest OS users to cause a denial of service (host OS panic or hang) by triggering many #DB (aka Debug) exceptions, related to svm.c. | |||||
| CVE-2020-27673 | 4 Debian, Linux, Opensuse and 1 more | 4 Debian Linux, Linux Kernel, Leap and 1 more | 2023-08-22 | 4.9 MEDIUM | 5.5 MEDIUM |
| An issue was discovered in the Linux kernel through 5.9.1, as used with Xen through 4.14.x. Guest OS users can cause a denial of service (host OS hang) via a high rate of events to dom0, aka CID-e99502f76271. | |||||
| CVE-2021-28689 | 1 Xen | 1 Xen | 2023-08-08 | 2.1 LOW | 5.5 MEDIUM |
| 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 virtualization. In AMD64, Xen had to use a different implementation approach, so Xen does not use ring 1 to support 64-bit guests. With the focus now being on 64-bit systems, and the availability of explicit hardware support for virtualization, fixing speculation issues in ring 1 is not a priority for processor companies. Indirect Branch Restricted Speculation (IBRS) is an architectural x86 extension put together to combat speculative execution sidechannel attacks, including Spectre v2. It was retrofitted in microcode to existing CPUs. For more details on Spectre v2, see: http://xenbits.xen.org/xsa/advisory-254.html However, IBRS does not architecturally protect ring 0 from predictions learnt in ring 1. For more details, see: https://software.intel.com/security-software-guidance/deep-dives/deep-dive-indirect-branch-restricted-speculation Similar situations may exist with other mitigations for other kinds of speculative execution attacks. The situation is quite likely to be similar for speculative execution attacks which have yet to be discovered, disclosed, or mitigated. | |||||
| CVE-2018-14678 | 4 Canonical, Debian, Linux and 1 more | 4 Ubuntu Linux, Debian Linux, Linux Kernel and 1 more | 2023-02-24 | 7.2 HIGH | 7.8 HIGH |
| An issue was discovered in the Linux kernel through 4.17.11, as used in Xen through 4.11.x. The xen_failsafe_callback entry point in arch/x86/entry/entry_64.S does not properly maintain RBX, which allows local users to cause a denial of service (uninitialized memory usage and system crash). Within Xen, 64-bit x86 PV Linux guest OS users can trigger a guest OS crash or possibly gain privileges. | |||||
| CVE-2013-0151 | 1 Xen | 1 Xen | 2023-02-13 | 4.6 MEDIUM | N/A |
| The do_hvm_op function in xen/arch/x86/hvm/hvm.c in Xen 4.2.x on the x86_32 platform does not prevent HVM_PARAM_NESTEDHVM (aka nested virtualization) operations, which allows guest OS users to cause a denial of service (long-duration page mappings and host OS crash) by leveraging administrative access to an HVM guest in a domain with a large number of VCPUs. | |||||