From: "Arch Linux: Recent news updates: David Runge" arch-announce@lists.archlinux.org
TL;DR: Upgrade your systems and container images now!
As many of you may have already read 1, the upstream release tarballs for xz in version 5.6.0 and 5.6.1 contain malicious code which adds a backdoor.
This vulnerability is tracked in the Arch Linux security tracker 2.
The xz packages prior to version 5.6.1-2 (specifically 5.6.0-1 and 5.6.1-1) contain this backdoor.
We strongly advise against using affected release artifacts and instead downloading what is currently available as latest version!
Upgrading the system
It is strongly advised to do a full system upgrade right away if your system currently has xz version 5.6.0-1 or 5.6.1-1 installed:
pacman -Syu
Regarding sshd authentication bypass/code execution
From the upstream report 1:
> openssh does not directly use liblzma. However debian and several other
distributions patch openssh to support systemd notification, and libsystemd
does depend on lzma.
Arch does not directly link openssh to liblzma, and thus this attack vector is not possible. You can confirm this by issuing the following command:
ldd "$(command -v sshd)"
However, out of an abundance of caution, we advise users to remove the malicious code from their system by upgrading either way. This is because other yet-to-be discovered methods to exploit the backdoor could exist.
URL: https://archlinux.org/news/the-xz-package-has-been-backdoored/
When upgrading from budgie-desktop 10.7.2-5 to 10.7.2-6, the package mutter43 must be replaced with magpie-wm, which currently depends on mutter. As mutter43 conflicts with mutter, manual intervention is required to complete the upgrade.
First remove mutter43, then immediately perform the upgrade. Do not relog or
reboot between these steps.
pacman -Rdd mutter43
pacman -Syu
From Arch:
The openblas package prior to version 0.3.23-2 doesn't ship optimized
LAPACK routine and CBLAS/LAPACKE interfaces for compatibility. This
decision has been reverted now, and the ability to choose a different
default system BLAS/LAPACK implementation while keeping openblas
installed is now provided to allow future co-installation of BLIS,
ATLAS, etc.
The default BLAS implementation will be used for most packages like
NumPy or R. Please install "blas-openblas" and "blas64-openblas" to make
OpenBLAS the default BLAS implementation, just like the old behavior.
Unfortunately you will get errors on updating if you currently have
OpenBLAS installed as ...
The base-devel package group has recently been replaced by a meta package of the same name.
People that had the base-devel package group installed (meaning people that installed base-devel before February 2nd) have to explicitly re-install it to get the new base-devel package installed on their system:
pacman -Syu base-devel
until https://bugs.archlinux.org/task/76440 is resolved
FS#76440 : systemd-cryptsetup still refers to libcrypto.so.1.1 after upgrading to openssl3
see: https://labs.parabola.nu/issues/3368
UPDATE 2022-11-08: fixed in cryptsetup 2.5.0-4
