New maintenance update candidates for XCP-ng 8.3 LTS

This release batch contains mostly fixes, tool version updates, and some improvements.

What changed

Virtualization & System

• kernel:

  • Reliability fixes for CVE-2026-45840 and CVE-2026-53227.
  • On some systems, PCIe expansion cards connected to a hotplug-capable PCI bus might not be seen at boot time. This release fixes such systems.
  • Fixed CVE-2026-64600, also known as RefluXFS. By default, XCP-ng doesn’t use XFS; when an XFS SR is used, we consider the LPE risk low, but fixed it anyway as a defence-in-depth measure.

• xen:

  • Synchronization with XenServer release 4.17.6-12:
    • Various XSA fixes that were already included in XCP-ng previous releases are now part of this XS release.
    • It also brings fixes for possible bugs and crashes.
  • Fix bug causing UEFI logic to set inappropriate screen resolutions.

• edk2: Add XCP-ng branding to the UEFI VM boot logo

• varstored and xcp-efivar-utils:

  • Sync with XenServer 1.3.4-2.
  • Group existing EFI helper scripts into a shared package xcp-efivar-utils.
  • Update dbx hashes from secureboot_objects v1.6.5.

• xcp-emu-manager: Stability fixes for aborting live migration and pausing a migrated VM to finalize the migration.

• xcp-ng-generic-lib: Fix build that was failing because of cmake3 update

Control Plane

• xapi:

  • Improve error reporting when pool join fails on TLS verification
  • Disallow PCI passthrough for boot devices, which would break dom0 boot
  • Add DHCP setting for VIF IP configuration, currently only supported by the Windows guest agent
  • Allow selecting image format (VHD, QCOW2) for VDIs during migration
  • Ensure the xapi database is flushed when shutting down
  • Add VLAN filtering support in XAPI.
  • Reuse sessions of storage backends, reducing the load on the database
  • Fixed cross-pool migration being blocked for VMs that couldn't be booted on the sender pool
  • Fixed wrong task timeout calculation for VMs with a large number of VBDs (and similar multi-part tasks)

• xcp-ng-xapi-plugins:

  • in sdncontroller.py plugin, fix dump-flows command when calling it against VLAN interface.
  • in sdncontroller.py plugin, fix add-rule command in edge case (error out instead of cleanly quit).

• xsconsole:

  • Retry the xapi connection instead of latching it broken forever
  • Add the option not to rename the management interface when performing an emergency network reset
  • Reset the old management interface IP configuration when switching to a new interface with the same IP address

Storage

• blktap: Fixes and log improvement

  • Stabilization fixes on qcow2 release:
    • Fix a potential deadlock on VDI export.
    • Fix a potential crash that could be invisible to the user because it could happen on the VDI close.
    • Fix a wrong VDI statistics computation.
  • tap-ctl commands now displays clear and parsable error messages.

• sm: Storage driver performance and stability have been significantly improved (QCOW2),

  • Drivers improvements + perf:
    - Add live leaf coalesce support for QCOW2 to avoid bump in size error.
    - Improve performance of scan on LVMSR with QCOW2 VDIs.
    - Reduce read cost of FileSR VDI allocated size during scan. Speed improvement for QCOW2: x10.
  • Drivers misc:
    • Robustify drivers: they have now an internal supported image format list.
    • Preserve image-format field during resize on FileSR.
    • Fix wrong data in LVMSR MGT: always store snapshot UUID instead of OpaqueRef.
    • Fixed a wrongful termination of the GC when having multiple openers of chain of VHD.
  • LINSTOR:
    • Improve LINSTOR perf: don't load VDIs during VDI.deactivate call.
    • Fix a bad LINSTOR snap rollback caused by a journaler race condition.
    • Improve performance of the LINSTOR Journaler by using the existing connection to the controller to avoid re-parsing the URI.
    • Fix a race condition in LINSTOR SR when trying to perform a snapshot while the same VDI is currently coalescing
  • To help recovering from a LINSTOR database corruption, it is now backed up regularly and after every major operation, locally on the master, and on the replicated LINSTOR database device.
  • Upstream changes:
    • Ignore LVM VDI missing from VGs and XAPI: prevent abort during scan.
    • SCSI volumes: resolve device names correctly using canonical device path(s). Some volumes were not resolved correctly.
    • Explain errors when a LUN cannot be resized.
    • Code optimization and cleanup.
    • Ignore LVM VDI missing from VGs and XAPI: prevent abort during scan.
    • SCSI volumes: resolve device names correctly using canonical device path(s). Some volumes were not resolved correctly.
    • Explain errors when a LUN cannot be resized.
    • Code optimization and cleanup.
    • Improved handling of wrongful metadata stored on VDI following an error.
    • Robustified tapdisk pause mechanism.

Regarding this sm update, please check whether the SM logs show any crashes related to the GC, particularly on NFS SRs, and send us these logs if there are any issues.

Network

• ca-certificates: Refresh root certificates to connect to third parties depending on Certificate Authorities.

• krb5: The Kerberos 5 library has been updated to improve GSSAPI compatibility to prepare upcoming packages upgrade (and to satisfy XS-8.4 migration).

• libreswan: Addressed DoS vulnerabilities (CVE-2026-12413, CVE-2026-50721, CVE-2026-50722) in encrypted Global Private Networks. Exposure appears minimal for XCP-ng environments, as OVS handles the underlying Libreswan orchestration directly.

• openssh: Fix regression and apply security patches.

  • Custom OpenSSH configurations will now be applied (custom rules are placed in /etc/ssh/sshd_config.d/. The files must end with .conf suffix)
  • Five minor security flaws have been fixed in OpenSSH:
    • CVE-2025-32728: A logic error was fixed regarding cases where x11_forwarding is disabled.
    • CVE-2025-61984: Checks for forbidden characters have been tightened.
    • CVE-2025-61985: A specific character has been disallowed in URL-encoded strings.
    • CVE-2026-35385: The behavior when using scp with -O (without -p) has been corrected to prevent privilege escalation.
    • CVE-2026-35388: The behavior regarding "ask/autoask" or ssh -O proxy ... has been corrected.

• p11-kit: - Updated library to prepare upcoming packages upgrade.

UI

• xo-lite: Update to 0.24.0-1

  • [System] Update system pages layout (user feedback) (PR #9746)

  • Introduce robots.txt for avoid browser indexing (PR #9858)

  • Update the UiTitle component to use the one from web-core (PR #9869)

  • [Pool/System] Add Reboot VM on internal shutdown in pool's system tab (PR #9962)

  • Update the UiCard component to use the one from web-core (PR #9980)

  • Update the UiCardTitle component to use the one from web-core (PR #9982)

  • Replacement of the UiSeparator component with VtsDivider from web-core (PR #10017)

  • Update side panels (PR #9836)

  • [XOA deploy] Update log visualization component (PR #9995)

  • [SidePanels] Add and use new VtsCardObjectTitle component to display object title and ID in side panels (PR #9755)

  • Replacement of the UiSpinner component with UiLoader from web-core (PR #10023)

  • [Pool,Host/Storage] Add Storage tabs (PR #10005)

  • [Host/dashboard] Switch CPU and RAM panels order to match Pool dashboard layout (PR #10059)

  • Remove all "coming soon" disabled button placeholders from network, VM, and pool components (PR #10068)

  • [VM/Network] add possibility to “connect/disconnect” a VIF on a VM (PR #10080)

  • [Pool/networks] Add the possibility to copy information from one or more networks in JSON format (PR #10083)

  • Fix some design inconsistency between pages (PR #10109)
    Update of the xo-lite RPM to version 0.23.0 at the request of the XO team.

  • [System] Update system pages layout (user feedback) (PR #9746)

  • Introduce robots.txt for avoid browser indexing (PR #9858)

  • Update the UiTitle component to use the one from web-core (PR #9869)

  • [Pool/System] Add Reboot VM on internal shutdown in pool's system tab (PR #9962)

  • Update the UiCard component to use the one from web-core (PR #9980)

  • Update the UiCardTitle component to use the one from web-core (PR #9982)

  • Replacement of the UiSeparator component with VtsDivider from web-core (PR #10017)

  • Update side panels (PR #9836)

  • [XOA deploy] Update log visualization component (PR #9995)

  • [SidePanels] Add and use new VtsCardObjectTitle component to display object title and ID in side panels (PR #9755)

  • Replacement of the UiSpinner component with UiLoader from web-core (PR #10023)

  • [Pool,Host/Storage] Add Storage tabs (PR #10005)

Drivers and Firmware

• amd-microcode: Update to 2026-05-19 drop as redistributed by XenServer. Updated CPUs:

  • BRH-C1 00b00f21: 2025-10-17, rev 0b002161 -> 2025-10-17, rev 0b002162
  • BRHD-B0 00b10f10: 2025-10-17, rev 0b101058 -> 2025-10-17, rev 0b101059

• qlogic-fastlinq-alt_8_42: If encountering issue with the current driver versions (main or alt ones) on some older hardware, this alt_8_42 package is based on an older source version can be tested for better results.

Others

• bash: No impact on usability, just for packaging facilities
• gmp: Updated library to prepare upcoming packages upgrade.
• redhat-lsb: Align to XS: Drop unused sub packages
• zlib: No impact on usability, just for packaging facilities

Versions

• amd-microcode: 20251203-1.1.xcpng8.3 -> 20260519-1.1.xcpng8.3
• bash: 4.2.46-30.el7 -> 4.2.46-30.1.xcpng8.3
• blktap: 3.55.5-9.1.xcpng8.3 -> 3.55.5-9.3.xcpng8.3
• ca-certificates: 2021.2.50-72.el7_9 -> 2021.2.50-73.1.xcpng8.3
• edk2: 20220801-1.7.11.1.xcpng8.3 -> 20220801-1.7.11.2.xcpng8.3
• gmp: 6.0.0-15.el7 -> 6.2.1-8.1.xcpng8.3
• gpumon: 24.1.0-91.1.xcpng8.3 -> 24.1.0-96.1.xcpng8.3
• kernel: 4.19.19-8.0.46.6.xcpng8.3 -> 4.19.19-8.0.46.10.xcpng8.3
• krb5: 1.15.1-22.1.xcpng8.3 -> 1.21.3-4.1.xcpng8.3
• libreswan: 4.12-2.3.2.xcpng8.3 -> 4.12-2.3.3.xcpng8.3
• ocaml: 4.14.2-1.xcpng8.3 -> 4.14.4-1.xcpng8.3
• ocaml-findlib: 1.9.8-1.xcpng8.3 -> 1.9.8-1.1.xcpng8.3
• opam: 2.4.1-1.1.xcpng8.3 -> 2.5.2-1.1.xcpng8.3
• openssh: 9.8p1-1.2.4.xcpng8.3 -> 9.8p1-1.2.6.xcpng8.3
• p11-kit: 0.23.5-3.el7 -> 0.24.1-4.xcpng8.3
• perl-Archive-Tar: 1.92-3.el7
• qlogic-fastlinq-alt_8_42: 8.42.10.0-2.xcpng8.3
• redhat-lsb: 4.1-27.el7.centos.1 -> 4.1-28.2.1.xcpng8.3
• sm: 3.2.12-17.9.xcpng8.3 -> 3.2.12-23.4.xcpng8.3
• varstored: 1.3.2-2.1.xcpng8.3 -> 1.3.4-2.1.xcpng8.3
• xapi: 26.1.11-1.3.xcpng8.3 -> 26.1.16-1.1.xcpng8.3
• xcp-efivar-utils: 1.0.0-1.xcpng8.3
• xcp-emu-manager: 1.2.0-2.xcpng8.3 -> 1.2.1-2.xcpng8.3
• xcp-featured: 1.2.1-2.xcpng8.3 -> 1.2.1-4.xcpng8.3
• xcp-ng-generic-lib: 1.1.1-4.xcpng8.3 -> 1.1.1-5.xcpng8.3
• xcp-ng-xapi-plugins: 1.16.0-1.xcpng8.3 -> 1.17.0-1.xcpng8.3
• xen: 4.17.6-9.3.1.xcpng8.3 -> 4.17.6-12.2.xcpng8.3
• xo-lite: 0.21.0-1.xcpng8.3 -> 0.24.0-1.xcpng8.3
• xs-opam-repo: 6.99.0-1.4.xcpng8.3 -> 6.99.0-1.5.xcpng8.3
• xsconsole: 11.0.9.1-1.1.xcpng8.3 -> 11.0.9.1-1.3.xcpng8.3
• zlib: 1.2.7-17.el7 -> 1.2.7-17.1.xcpng8.3

Test on XCP-ng 8.3

yum clean metadata --enablerepo=xcp-ng-testing,xcp-ng-candidates
yum update --enablerepo=xcp-ng-testing,xcp-ng-candidates
reboot

The usual update rules apply: pool coordinator first, etc.

What to test

As usual, normal use and anything else you want to test.

Regarding this sm update, please check whether the SM logs show any crashes related to the GC, particularly on NFS SRs, and send us these logs if there are any issues.

Test window before official release of the updates

~ 4 days

We would like to thank users who shared feedback since our last call for testing:

@Andrew, @JeffBerntsen, @MajorP93, @TrapoSAMA, @acebmxer, @andersonalipio, @flakpyro, @marcoi