CVE-2023-3899

A vulnerability was found in subscription-manager that allows local privilege escalation due to inadequate authorization. The D-Bus interface com.redhat.RHSM1 exposes a significant number of methods to all users that could change the state of the registration. By using the com.redhat.RHSM1.Config.SetAll() method, a low-privileged local user could tamper with the state of the registration, by unregistering the system or by changing the current entitlements. This flaw allows an attacker to set arbitrary configuration directives for /etc/rhsm/rhsm.conf, which can be abused to cause a local privilege escalation to an unconfined root.

Mitigation

A workaround is to mask rhsm.service using:

systemctl mask rhsm.service  

When the rhsm.service is masked, then no D-Bus call cannot trigger the service and all D-Bus calls will be terminated with error: "Call failed: Could not activate remote peer." But then all applications using D-Bus API will not work until you unmask the service using: "systemctl unmask rhsm.service"