Arm guests can cause Dom0 DoS via PV devices

ISSUE DESCRIPTION When mapping pages of guests on Arm, dom0 is using an rbtree to keep track of the foreign mappings. Updating of that rbtree is not always done completely with the related lock held, resulting in a small race window, which can be used by unprivileged guests via PV devices to caus...

Hotfix XS82E034 - For Citrix Hypervisor 8.2

Who Should Install This Hotfix? This is a hotfix for customers running Citrix Hypervisor 8.2. Information About this Hotfix Component| Details ---|--- Prerequisite| None Post-update tasks| Restart Host Content live patchable| Yes Baselines for Live Patch| XS82E024, XS82E030 Revision History|...

Guest triggered use-after-free in Linux xen-netback

ISSUE DESCRIPTION A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux...

Oracle Linux 7 / 8 : Unbreakable Enterprise kernel-container (ELSA-2021-9038)

The remote Oracle Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2021-9038 advisory. - netfilter: add and use nfhookslowlist Florian Westphal Orabug: 32372530 CVE-2021-20177 - target: fix XCOPY NAA identifier lookup David Disseldorp...

Ubuntu 20.04 LTS : Linux kernel vulnerabilities (USN-4751-1)

The remote Ubuntu 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4751-1 advisory. It was discovered that the console keyboard driver in the Linux kernel contained a race condition. A local attacker could use this to expose sensitive...

CVE-2021-28039

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...

DEBIAN-CVE-2021-28039

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...

CVE-2021-28039

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...

CVE-2021-28039

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...

CVE-2021-28039

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...

CVE-2021-28039

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...

CVE-2021-28039

CVE-2021-28039 affects the Linux kernel 5.9.x–5.11.3 (used with Xen). In some configurations, an x86 PV guest OS user can crash the Dom0 or a driver domain by generating a large amount of I/O. Root cause is the misuse of guest physical addresses when CONFIG_XEN_UNPOPULATED_ALLOC is set but CONFIG...

CVE-2021-28039

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...

Linux: special config may crash when trying to map foreign pages

ISSUE DESCRIPTION With CONFIGXENBALLOONMEMORYHOTPLUG disabled and CONFIGXENUNPOPULATEDALLOC enabled the Linux kernel will use guest physical addresses allocated via the ZONEDEVICE functionality for mapping foreign guest's pages. This will result in problems, as the p2m list will only cover the...

Oracle Linux 7 / 8 : Unbreakable Enterprise kernel-container (ELSA-2021-9007)

The remote Oracle Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2021-9007 advisory. - xen-blkback: set ring-xenblkd to NULL after kthreadstop Pawel Wieczorkiewicz Orabug: 32260252 CVE-2020-29569 - xenbus/xenbusbackend: Disallow...

Ubuntu 16.04 LTS / 18.04 LTS : Linux kernel vulnerabilities (USN-4680-1)

The remote Ubuntu 16.04 LTS / 18.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4680-1 advisory. It was discovered that debugfs in the Linux kernel as used by blktrace contained a use-after-free in some situations. A privileged local...

Ubuntu 18.04 LTS / 20.04 LTS : Linux kernel vulnerabilities (USN-4679-1)

The remote Ubuntu 18.04 LTS / 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4679-1 advisory. It was discovered that the console keyboard driver in the Linux kernel contained a race condition. A local attacker could use this to expose...

Xen oxenstored DoS (XSA-352)

According to its self-reported version number, the Xen hypervisor installed on the remote host is affected by a denial of service vulnerability due to an issue with oxenstored. A malicious guest administrator can change xenstore node ownership to run another guest out of quota, or create an...

Design/Logic Flaw

An issue was discovered in Xen XAPI before 2020-12-15. Certain xenstore keys provide feedback from the guest, and are therefore watched by toolstack. Specifically, keys are watched by xenopsd, and data are forwarded via RPC through message-switch to xapi. The watching logic in xenopsd sends one R...

UBUNTU-CVE-2020-29569

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...