A xen security update has been released for Fedora 33.

SECURITY: Fedora 33 Update: xen-4.14.0-9.fc33

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Fedora Update Notification
FEDORA-2020-ec84c1565b
2020-11-12 03:05:39.155788
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Name : xen
Product : Fedora 33
Version : 4.14.0
Release : 9.fc33
URL :   http://xen.org/
Summary : Xen is a virtual machine monitor
Description :
This package contains the XenD daemon and xm command line
tools, needed to manage virtual machines running under the
Xen hypervisor

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Update Information:

revised patch for XSA-286 (mitigating performance impact) ---- x86 PV guest
INVLPG-like flushes may leave stale TLB entries [XSA-286, CVE-2020-27674]
(#1891092) simplify grub scripts (patches from Thierry Vignaud
) some fixes for gcc 11
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ChangeLog:

* Tue Nov 3 2020 Michael Young - 4.14.0-9
- revised patch for XSA-286 (mitigating performance impact)
* Fri Oct 30 2020 Jeff Law - 4.14.0-8
- Work around gcc-11 stringop-overflow diagnostics as well
* Wed Oct 28 2020 Michael Young - 4.14.0-7
- x86 PV guest INVLPG-like flushes may leave stale TLB entries
[XSA-286, CVE-2020-27674] (#1891092)
- simplify grub scripts (patches from Thierry Vignaud )
- some fixes for gcc 11
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References:

[ 1 ] Bug #1891089 - CVE-2020-27674 xen: x86 PV guest INVLPG-like flushes may leave stale TLB entries (XSA-286)
  https://bugzilla.redhat.com/show_bug.cgi?id=1891089
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This update can be installed with the "dnf" update program. Use
su -c 'dnf upgrade --advisory FEDORA-2020-ec84c1565b' at the command
line. For more information, refer to the dnf documentation available at
  http://dnf.readthedocs.io/en/latest/command_ref.html#upgrade-command-label

All packages are signed with the Fedora Project GPG key. More details on the
GPG keys used by the Fedora Project can be found at
  https://fedoraproject.org/keys