A xen security update has been released for Fedora 33.

SECURITY: Fedora 33 Update: xen-4.14.3-2.fc33

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Fedora Update Notification
FEDORA-2021-0b7a484688
2021-10-15 18:53:33.324102
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Name : xen
Product : Fedora 33
Version : 4.14.3
Release : 2.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:

PCI devices with RMRRs not deassigned correctly [XSA-386, CVE-2021-28702]
(#2011248)
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ChangeLog:

* Wed Oct 6 2021 Michael Young - 4.14.3-2
- PCI devices with RMRRs not deassigned correctly [XSA-386, CVE-2021-28702]
(#2011248)
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References:

[ 1 ] Bug #2011247 - CVE-2021-28702 xen: administrators of guests which have been assigned RMRR-using PCI devices can cause DoS
  https://bugzilla.redhat.com/show_bug.cgi?id=2011247
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This update can be installed with the "dnf" update program. Use
su -c 'dnf upgrade --advisory FEDORA-2021-0b7a484688' 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