A systemd security update has been released for Arch Linux.

Arch Linux Security Advisory ASA-202002-8
========================================
Severity: High
Date : 2020-02-12
CVE-ID : CVE-2020-1712
Package : systemd
Type : privilege escalation
Remote : No
Link :   https://security.archlinux.org/AVG-1094

Summary
======
The package systemd before version 244.2-1 is vulnerable to privilege
escalation.

Resolution
=========
Upgrade to 244.2-1.

# pacman -Syu "systemd>$4.2-1"

The problem has been fixed upstream in version 244.2.

Workaround
=========
None.

Description
==========
A heap use-after-free vulnerability was found in systemd before version
244.2, where asynchronous Polkit queries are performed while handling
dbus messages. A local unprivileged attacker can abuse this flaw to
crash systemd services or potentially execute code and elevate their
privileges, by sending specially crafted dbus messages.

Impact
=====
A local unprivileged attacker is able to crash the system or execute
arbitrary code as root by abusing polkit caching mechanisms.

References
=========
  https://github.com/systemd/systemd/commit/ea0d0ede03c6f18dbc5036c5e9cccf97e415ccc2
  https://github.com/systemd/systemd-stable/commit/e2d4cb9843c50eff76e9104fec6b448c0d7c8814
  https://security.archlinux.org/CVE-2020-1712