Xinuos (formerly SCO) Openserver v5 and v6 allows attackers to execute arbitrary commands via shell metacharacters in outputform or toclevels parameter to cgi-bin/printbook.

An issue has been identified in both XenServer 8 and Citrix Hypervisor 8.2 CU1 LTSR which may allow a malicious administrator of a guest VM to cause the host to become slow and/or unresponsive.

A reflected Cross-site scripting (XSS) vulnerability in Xinuo (formerly SCO) Openserver version 5 and 6 allows remote attackers to inject arbitrary web script or HTML tag via the parameter 'section'.

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.

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.

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.

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.

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.

Citrix XenServer 7.1 and newer allows Directory Traversal.

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.