CVE-2020-27671

A flaw was found to occur in the Xen optimization to coalesce per-page IOMMU TLB flushes. This flaw allows malicious x86 HVM and PVH guests to cause host data corruption and data leaks, resulting in a denial of service (DoS) or potential privilege escalation. The highest threat from this vulnerability is to confidentiality and integrity as well as system availability.

Mitigation

Avoid passing through physical devices to untrusted guests. Refer to the XSA-346 advisory for additional information.