USN-4269-1: systemd vulnerabilities

05 February 2020

Several security issues were fixed in systemd.

Releases

Packages

  • systemd - system and service manager

Details

It was discovered that systemd incorrectly handled certain PIDFile files.
A local attacker could possibly use this issue to trick systemd into
killing privileged processes. This issue only affected Ubuntu 16.04 LTS.
(CVE-2018-16888)

It was discovered that systemd incorrectly handled certain udevadm trigger
commands. A local attacker could possibly use this issue to cause systemd
to consume resources, leading to a denial of service. (CVE-2019-20386)

Jann Horn discovered that systemd incorrectly handled services that use the
DynamicUser property. A local attacker could possibly use this issue to
access resources owned by a different service in the future. This issue
only affected Ubuntu 18.04 LTS. (CVE-2019-3843, CVE-2019-3844)

Tavis Ormandy discovered that systemd incorrectly handled certain Polkit
queries. A local attacker could use this issue to cause systemd to crash,
resulting in a denial of service, or possibly execute arbitrary code and
escalate privileges. (CVE-2020-1712)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 19.10
Ubuntu 18.04
Ubuntu 16.04

After a standard system update you need to reboot your computer to make
all the necessary changes.