A systemd security update has been released for Ubuntu Linux 19.10, 18.04 LTS, and 16.04 LTS.
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Ubuntu Security Notice USN-4269-1
February 05, 2020
systemd vulnerabilities
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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
After a standard system update you need to reboot your computer to make
all the necessary changes.
References:
https://usn.ubuntu.com/4269-1
CVE-2018-16888, CVE-2019-20386, CVE-2019-3843, CVE-2019-3844,
CVE-2020-1712
Package Information:
https://launchpad.net/ubuntu/+source/systemd/242-7ubuntu3.6
https://launchpad.net/ubuntu/+source/systemd/237-3ubuntu10.38
https://launchpad.net/ubuntu/+source/systemd/229-4ubuntu21.27