CVE-2026-4105: Systemd: systemd: privilege escalation via improper access control in registermachine d-bus method

Severity: medium (CVSS 6.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-13 · updated 2026-09-01
Weakness: CWE-284

Description

A flaw was found in systemd. The systemd-machined service contains an Improper Access Control vulnerability due to insufficient validation of the class parameter in the RegisterMachine D-Bus (Desktop Bus) method. A local unprivileged user can exploit this by attempting to register a machine with a specific class value, which may leave behind a usable, attacker-controlled machine object. This allows the attacker to invoke methods on the privileged object, leading to the execution of arbitrary commands with root privileges on the host system.

Affected products

Red Hat OpenShift Container Platform 4.18: all versions
Red Hat Enterprise Linux 10: all versions
Red Hat Enterprise Linux 7: all versions
Red Hat Enterprise Linux 8: all versions
Red Hat Enterprise Linux 9: all versions
Red Hat Hardened Images: all versions — fixed in 260.1-2.1.hum1

How to fix

Upgrade to a fixed version: Red Hat Hardened Images 260.1-2.1.hum1. Check the vendor advisory for mitigations.

References

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