USN-4269-1: systemd vulnerabilities

5 February 2020

systemd vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 19.10
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS

Summary

Several security issues were fixed in systemd.

Software Description

  • 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
systemd - 242-7ubuntu3.6
Ubuntu 18.04 LTS
systemd - 237-3ubuntu10.38
Ubuntu 16.04 LTS
systemd - 229-4ubuntu21.27

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References