CVE-2020-29486

An issue was discovered in Xen through 4.14.x. Nodes in xenstore have an
ownership. In oxenstored, a owner could give a node away. However, node
ownership has quota implications. Any guest can run another guest out of
quota, or create an unbounded number of nodes owned by dom0, thus running
xenstored out of memory A malicious guest administrator can cause a denial
of service against a specific guest or against the whole host. All systems
using oxenstored are vulnerable. Building and using oxenstored is the
default in the upstream Xen distribution, if the Ocaml compiler is
available. Systems using C xenstored are not vulnerable.

Notes