Debian: DSA-4274-1 Severe: L1 Terminal Fault Denial Of Service Issues

This update provides mitigations for the "L1 Terminal Fault"
vulnerability affecting a range of Intel CPUs.

For additional information please refer to
https://xenbits.xen.org/xsa/advisory-273.html. The microcode updates
mentioned there are not yet available in a form distributable by Debian.

In addition two denial of service vulnerabilities have been fixed
(XSA-268 and XSA-269).

For the stable distribution (stretch), these problems have been fixed in
version 4.8.4+xsa273+shim4.10.1+xsa273-1+deb9u10.

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/