Kernel: FPU state information leakage via lazy FPU restore

System software utilizing Lazy FP state restore technique on systems using Intel Core-based microprocessors may potentially allow a local process to infer data from another process through a speculative execution side channel.

xen: x86: DoS from attempting to use INVPCID with a non-canonical addresses

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.

xen: insufficient TLB flushing / improper large page mappings with AMD IOMMUs

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.

xen: insufficient TLB flushing / improper large page mappings with AMD IOMMUs

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.

Citrix XenServer 7.1 and newer allows Directory Traversal.

iSM: Dell EMC iDRAC Service Module Improper File Permission Vulnerability

Dell EMC iDRAC Service Module for all supported Linux and XenServer versions v3.0.1, v3.0.2, v3.1.0, v3.2.0, when started, changes the default file permission of the hosts file of the host operating system (/etc/hosts) to world writable. A malicious low privileged operating system user or process could modify the host file and potentially redirect traffic from the intended destination to sites hosting malicious or unwanted content.

Qemu: display: cirrus: potential arbitrary code execution via cirrus_bitblt_cputovideo

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.

Qemu: display: cirrus: oob access while doing bitblt copy backward mode

Quick emulator (QEMU) built with the Cirrus CLGD 54xx VGA emulator support is vulnerable to an out-of-bounds access issue. It could occur while copying VGA data via bitblt copy in backward mode. A privileged user inside a guest could use this flaw to crash the QEMU process resulting in DoS or potentially execute arbitrary code on the host with privileges of QEMU process on the host.

Qemu: cirrus: heap buffer overflow via vnc connection

A heap buffer overflow flaw was found in QEMU's Cirrus CLGD 54xx VGA emulator's VNC display driver support before 2.9; the issue could occur when a VNC client attempted to update its display after a VGA operation is performed by a guest. A privileged user/process inside a guest could use this flaw to crash the QEMU process or, potentially, execute arbitrary code on the host with privileges of the QEMU process.

The Windows Guest Tools in Citrix XenServer 6.2 SP1 and earlier allows remote attackers to cause a denial of service (guest OS crash) via a crafted Ethernet frame.

Citrix XenServer 4.1, 6.0, 5.6 SP2, 5.6 Feature Pack 1, 5.6 Common Criteria, 5.6, 5.5, 5.0, and 5.0 Update 3 contains a Local Privilege Escalation Vulnerability which could allow local users with access to a guest operating system to gain elevated privileges.