Debian: DSA-4812-1 Urgent: Xen Denial of Service and Information Leak

Multiple vulnerabilities have been discovered in the Xen hypervisor:

Several security issues affecting Xenstore could result in cross
domain access (denial of service, information leaks or privilege
escalation) or denial of service against xenstored.

Additional vulnerabilities could result in guest-to-host denial of
service.

For the stable distribution (buster), these problems have been fixed in
version 4.11.4+57-g41a822c392-2.

We recommend that you upgrade your xen packages.

For the detailed security status of xen please refer to
its security tracker page at:
https://security-tracker.debian.org/tracker/source-package/xen

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at: https://www.debian.org/security/