CVE-2019-3842

Publication date 8 April 2019

Last updated 25 August 2025

Ubuntu priority

Cvss 3 Severity Score

Description

In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using the "allow_active" element rather than "allow_any".

Status

Show unmaintained releases

Package	Ubuntu Release	Status
systemd	18.10 cosmic	Fixed 239-7ubuntu10.12
	18.04 LTS bionic	Fixed 237-3ubuntu10.19
	16.04 LTS xenial	Fixed 229-4ubuntu21.21
	14.04 LTS trusty	Fixed 204-5ubuntu20.31

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
systemd	Upstream: 83d4ab5

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.0 · High

Base metrics

Parameter	Value
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High

Scores

Parameter	Value
Base score	7.0 · High
Exploitability score	-
Impact score	-

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

References

Related Ubuntu Security Notices (USN)

USN-3938-1
systemd vulnerability
8 April 2019

Other references

https://www.cve.org/CVERecord?id=CVE-2019-3842