Debian Stretch: DSA-4444-1: Serious Intel Data Exposure Found

See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html
for more details.

To fully resolve these vulnerabilities it is also necessary to install
updated CPU microcode. An updated intel-microcode package (only
available in Debian non-free) will be provided via a separate DSA. The
updated CPU microcode may also be available as part of a system firmware
("BIOS") update.

In addition, this update includes a fix for a regression causing
deadlocks inside the loopback driver, which was introduced by the update
to 4.9.168 in the last Stretch point release.

For the stable distribution (stretch), these problems have been fixed in
version 4.9.168-1+deb9u2.

We recommend that you upgrade your linux packages.

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

Further information about Debian Security Advisories, how to apply
these updates to your system and frequently asked questions can be
found at...