A xen security update has been released for Fedora 33.

SECURITY: Fedora 33 Update: xen-4.14.2-3.fc33

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Fedora Update Notification
FEDORA-2021-4f129cc0c1
2021-09-05 21:26:52.079108
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Name : xen
Product : Fedora 33
Version : 4.14.2
Release : 3.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:

IOMMU page mapping issues on x86 [XSA-378, CVE-2021-28694, CVE-2021-28695,
CVE-2021-28696] (#1997531) (#1997568) (#1997537) grant table v2 status pages may
remain accessible after de-allocation [XSA-379, CVE-2021-28697] (#1997520) long
running loops in grant table handling [XSA-380, CVE-2021-28698] (#1997526)
inadequate grant-v2 status frames array bounds check [XSA-382, CVE-2021-28699]
(#1997523) xen/arm: No memory limit for dom0less domUs [XSA-383, CVE-2021-28700]
(#1997527) grub x86_64-efi modules now go into /boot/grub2
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ChangeLog:

* Sat Aug 28 2021 Michael Young - 4.14.2-3
- IOMMU page mapping issues on x86 [XSA-378, CVE-2021-28694,
CVE-2021-28695, CVE-2021-28696] (#1997531) (#1997568)
(#1997537)
- grant table v2 status pages may remain accessible after de-allocation
[XSA-379, CVE-2021-28697] (#1997520)
- long running loops in grant table handling [XSA-380, CVE-2021-28698]
(#1997526)
- inadequate grant-v2 status frames array bounds check [XSA-382,
CVE-2021-28699] (#1997523)
- xen/arm: No memory limit for dom0less domUs [XSA-383, CVE-2021-28700]
(#1997527)
- grub x86_64-efi modules now go into /boot/grub2
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References:

[ 1 ] Bug #1997519 - CVE-2021-28697 xen: malicious guest may be able to elevate its privileges leads to DoS
  https://bugzilla.redhat.com/show_bug.cgi?id=1997519
[ 2 ] Bug #1997522 - CVE-2021-28699 xen: malicious guest kernel leads to DoS
  https://bugzilla.redhat.com/show_bug.cgi?id=1997522
[ 3 ] Bug #1997524 - CVE-2021-28698 xen: malicious kernels lead to DoS
  https://bugzilla.redhat.com/show_bug.cgi?id=1997524
[ 4 ] Bug #1997525 - CVE-2021-28700 xen: malicious dom0less guest could drive Xen out of memory and leads to DoS
  https://bugzilla.redhat.com/show_bug.cgi?id=1997525
[ 5 ] Bug #1997529 - CVE-2021-28694 xen: failed to prevent guests from undoing/replacing such mappings
  https://bugzilla.redhat.com/show_bug.cgi?id=1997529
[ 6 ] Bug #1997535 - CVE-2021-28696 xen: physical device from a guest allowing to access memory
  https://bugzilla.redhat.com/show_bug.cgi?id=1997535
[ 7 ] Bug #1997567 - CVE-2021-28695 xen: discontinuous range is specified by firmware leads to vulnerability
  https://bugzilla.redhat.com/show_bug.cgi?id=1997567
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This update can be installed with the "dnf" update program. Use
su -c 'dnf upgrade --advisory FEDORA-2021-4f129cc0c1' 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