Updates announcements and testing

bleader

New security update candidate (xen)

Three new XSAs were published on 9th of April.

Notes:

XSA-456 was published on various public mailing list but its entry is not yet on the xenbits page, hence the different link for this one.
XSAs description to be completed later, early posting to provide more chances to run tests before final release.

XSA-454 impacts all host running HVM or PVH guests on x86_64, therefore all supported architectures on XCP-ng.
XSA-455 relates to XSA-407 (Branch Type Confusion) having a logical error, check its VULNERABLE SYSTEMS section for impacted systems.
XSA-456 should only impact Intel CPU as it is understood at this time.

SECURITY UPDATES

xen-*:
- Fix XSA-454 - x86 HVM hypercalls may trigger Xen bug check. HVM and PVH guests can DoS a host in some cases calling 32-bit-mode hypercalls with parameters that will lead the hypercall sanity checks to trigger a crash.
- Fix XSA-455 - x86: Incorrect logic for BTC/SRSO mitigations. Fix for XSA-407 was not properly used, meaning an attacker could be able to infer memory from host or other guests. All versions since 4.13.4-9.24.1 are vulnerable.
- Fix XSA-456 - x86: Native Branch History Injection. An attacker could infer memory of host or other guests by using the Native Branch History Ijnection flaw. This is an evolution of Spectre-BHB which was previously considered not to be a risk for Xen.

Test on XCP-ng 8.2

yum clean metadata --enablerepo=xcp-ng-testing
yum update "xen-*" --enablerepo=xcp-ng-testing
reboot

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

Versions:

xen: 4.13.5-9.40.1.xcpng8.2

What to test

Normal use and anything else you want to test.

Test window before official release of the updates

~1 days because of security updates.

Andrew

@bleader Did they get published to the right directory? I don't see anything in testing (stuff is in incoming).

bleader

My bad, we were a bit late and I tried to be quick and forgot to move it... Just did that, should be good soon, it needs some time to sync repos.

olivierlambert

Tested in my home lab, no explosion

gskger

@bleader Updated my homelab without any issues

JeffBerntsen

@bleader Seems to be running just fine on my test servers as well.

Andrew

@bleader Installed and running.

stormi

Now live. Thanks everyone!

https://xcp-ng.org/blog/2024/04/13/april-2024-security-update/

stormi

New update candidates for you to test!

As you may know, we group non-urgent updates together for a collective release, in order not to cause unnecessary maintenance for our users.

The moment to release such a batch has come, grouped with a recent security fix, so here they are, ready for user tests before the final release.

qemu: security fix to protect hosts from DoS that can be caused by a malicious administrator of a guest (XenServer security bulletin)
openssh: rebased on CentOS 7's openssh-7.4p1-23.el7_9 to fix various CVEs. The update also changes the way default ciphers and algorithms are set. See dedicated section below.
curl: updated to version 8.6.0 + patches, to fix several CVEs. Note: in XCP-ng, curl is mostly used by yum for downloading RPMs when updating hosts.
sudo: updated to a recent release to fix some CVEs (none critical in the context of XCP-ng as far as we can tell)
Note : XenServer published updates for openssh, curl and sudo together as hotfix XS82ECU1063, whose only description is "This hotfix includes upstream code changes that may reduce false-positive reports for the following CVEs: CVE-2023-38545, CVE-2023-48795 and CVE-2023-28486." We are not sure what this "false-positive reports" statement means, but what appears to us is that anyway the CVEs fixed were clearly either not exploitable, or not critical, in the context of XCP-ng.
microcode_ctl: updated to Intel's IPU 2024.2 release, + a fix to Gemini Lake 06-7a-01 for a regression that was introduced by IPU 2024.1 (see this forum thread and this one too)
linux-firmware: updated AMD firmware to the 2024-05-03 drop. What fixes this contains exactly is not described.
XAPI and related components: synced with Citrix Hypervisor hotfixes XS82ECU1064 and XS82ECU1053. Various fixes. Check the hotfixes descriptions.
- We also added a fix to make the small web server managed by XAPI report accurate mimetypes for files it serves. This is important for XO Lite (which is not installed by default on XCP-ng 8.2, but can be if you need it).
tzdata: updated timezone data.
sm: adds the new largeblock storage driver, which is a local SR driver which workarounds the current limitation our storage stack has with 4KiB-block-only devices, by transparently emulating a 512B block size (at some performance cost, obviously). More about it in this forum thread.
- Also rebased on Citrix Hypervisor's hotfix XS82ECU1065

About OpenSSH, Ciphers and algorithms

To ensure that the lists of authorized Ciphers, algorithms, etc., defined by XenServer's security team are applied, XenServer packagers had decided that any change they had to make would plainly overwrite /etc/ssh/sshd_config and /etc/ssh/ssh_config. Although we discourage customizing XCP-ng's configuration too far, we didn't think it would be acceptable for our users than these files be overwritten without any notice.

So we looked for another approach, and decided for this: we don't define these keys (Ciphers, MACs, KexAlgorithms, HostKeyAlgorithms) in the configuration files anymore. Now, we define them at build time, directly in the built binaries.

If you need to override them, you can still do so in the configuration files. But then this means you become responsible of their future update, whenever a cipher or algorithm starts being considered weak, as this will override the built-in settings defined by our security team.

The update process will attempt to be smart and will remove the definition of the above keys from /etc/ssh/sshd_config and /etc/ssh/ssh_config, but only if you had not touched these lines. If you have brought customizations to these keys, then we will leave them as they were. In this case, this means that any future change our security team may make to the built-in values will not be applied to your hosts, because your changes in the configuration files will override the built-ins.. If you are in this situation, you have to choose: either remove these lines manually, or make sure you keep them updated by yourself according to your security policy.

You can check what configuration is applied to your instance of sshd with: sshd -T.

Test on XCP-ng 8.2

From an up to date host:

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.

Versions

List based on source RPMs, which can differ from actual built RPMs (for example, the xapi source RPM, when built, produces xapi-core, xapi-xe and xapi-tests).

curl-8.6.0-2.1.xcpng8.2
forkexecd-1.18.3-10.1.xcpng8.2
gpumon-0.18.0-18.1.xcpng8.2
linux-firmware-20190314-11.1.xcpng8.2
message-switch-1.23.2-17.1.xcpng8.2
microcode_ctl-2.1-26.xs29.2.xcpng8.2
microsemi-smartpqi-alt-2.1.28_025-1.xcpng8.2
ocaml-rrd-transport-1.16.1-15.1.xcpng8.2
ocaml-rrdd-plugin-1.9.1-15.1.xcpng8.2
ocaml-tapctl-1.5.1-15.1.xcpng8.2
ocaml-xcp-idl-1.96.7-4.1.xcpng8.2
ocaml-xen-api-client-1.9.0-18.1.xcpng8.2
ocaml-xen-api-libs-transitional-2.25.6-7.1.xcpng8.2
openssh-7.4p1-23.2.1.xcpng8.2
qemu-4.2.1-4.6.4.1.xcpng8.2
rrd2csv-1.2.6-15.1.xcpng8.2
rrdd-plugins-1.10.9-12.1.xcpng8.2
sm-2.30.8-12.2.xcpng8.2
sm-cli-0.23.0-61.1.xcpng8.2
squeezed-0.27.0-18.1.xcpng8.2
sudo-1.9.15-2.1.xcpng8.2
tzdata-2024a-1.el7
varstored-guard-0.6.2-15.xcpng8.2
vhd-tool-0.43.0-18.1.xcpng8.2
wsproxy-1.12.0-19.xcpng8.2
xapi-1.249.36-1.1.xcpng8.2
xapi-nbd-1.11.0-17.1.xcpng8.2
xapi-storage-11.19.0_sxm2-17.xcpng8.2
xapi-storage-script-0.34.1-16.1.xcpng8.2
xcp-networkd-0.56.2-15.xcpng8.2
xcp-ng-release-8.2.1-11
xcp-rrdd-1.33.4-4.1.xcpng8.2
xenopsd-0.150.19-3.1.xcpng8.2

What to test

Normal use and anything else you want to test. The closer to your actual use of XCP-ng, the better.

Extra attention to:

SSH server, ciphers, configuration files
checking downloads with curl
sudo if you use it

Test window before official release of the updates

Release planned either on Friday 14th or Monday 17th.

olivierlambert

Update done here in my home lab, no issue

JeffBerntsen

Only one of my two systems will take the complete update, but that one is working just fine.

The other which I had used in the past as a test server for XOSTOR will not install the sm-2.30.8-12.1.xcpng8.2.x86_64 package looking for a dependency on sm-linstor and not finding it.

stormi

@JeffBerntsen Indeed, the update for XOSTOR is not ready yet. It will be before we release the updates, but I forgot about you testers

JeffBerntsen

@stormi Not a problem. I just wanted to make sure I hadn't done something wrong. As it is, the system is working with all of the updates but that one in place.

gskger

@stormi Update went well on my two node homelab. VMs and basic operations work as expected. Let's see how things go over the next days. Keep up the good work!

Andrew

@stormi Updated all my normal 8.2 systems updated. All working normally.

stormi

Thanks everyone for your tests!

We just published the updates: https://xcp-ng.org/blog/2024/06/17/june-2024-security-and-maintenance/

CJ

@stormi Are these going to be pushed to 8.3 or just part of the final release?

stormi

@CJ Everything that is relevant for XCP-ng 8.3 is either already built and ready to be pushed (you can pull from xcp-ng-candidates if you want it already), or being built/tested.

bleader

New security update candidate (xen, xapi, xsconsole)

Two new XSAs were published on 16th of July.

XSA-458 guests which have a multi-vector MSI capable device passed through to them can leverage the vulnerability.
XSA-459 impacts systems running Xapi v3.249.x, which means any up to date XCP-ng 8.2. Note this requires heavy crafting and likely social engineering on the attacker side, see the XSA's "VULNERABLE SYSTEMS" section for more details.

SECURITY UPDATES

xen-*:
- Fix XSA-458 - double unlock in x86 guest IRQ handling. When passing through a multi-vector MSI capable device to a guest, an attacker could use an error handling path that could lead to the issue, no exploitations results have been ruled out: Denial of Service (DoS), crashes, information leaks, or elevation of privilege could all be possible.
xapi, xsconsole:
- Fix XSA-459 - Xapi: Metadata injection attack against backup/restore functionality. A malicious guest can manipulate its disk to appear to be a metadata
  backup, then having about a 50% chance of appearing ahead of a legitimate metadata backup. The more disks the guest has, the higher the chances of this happening are.

Test on XCP-ng 8.2

yum clean metadata --enablerepo=xcp-ng-testing
yum update "xen-*" "xapi-*" xsconsole --enablerepo=xcp-ng-testing
reboot

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

Versions:

xen: xen-4.13.5-9.40.2.xcpng8.2
xapi: xapi-1.249.36-1.2.xcpng8.2
xsconsole: xsconsole-10.1.13-1.2.xcpng8.2

What to test

Normal use and anything else you want to test.

Test window before official release of the update

~ 1 day because of security updates.

olivierlambert

I suppose I need to be a bit more patient

No packages marked for update