When systemd-machined >= v259 (or v258 with a custom polkit policy that allows register-machine access) is running on a desktop system, an unprivileged user logged in a desktop graphical session can kill arbitrary processes, even privileged ones.
- versions older than v259 are not affected, unless unprivileged access is granted for the
register-machinepolkit action via a local, custom policy config file - versions older than v258 are not affected
- unrelated to the systemd service manager (pid 1 or user session managers)
- systemd-machined is not typically installed by default, and is typically in an optional, separate package (e.g.: systemd-container)
- terminal-only or remote sessions (e.g.: ssh) are not affected
Weakness
The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Systemd | Ubuntu | resolute | * |
Extended Description
Access control involves the use of several protection mechanisms such as:
When any mechanism is not applied or otherwise fails, attackers can compromise the security of the product by gaining privileges, reading sensitive information, executing commands, evading detection, etc. There are two distinct behaviors that can introduce access control weaknesses:
Potential Mitigations
- Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
- Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Related Attack Patterns
- https://cwe.mitre.org/data/definitions/19.html
- https://cwe.mitre.org/data/definitions/441.html
- https://cwe.mitre.org/data/definitions/478.html
- https://cwe.mitre.org/data/definitions/479.html
- https://cwe.mitre.org/data/definitions/502.html
- https://cwe.mitre.org/data/definitions/503.html
- https://cwe.mitre.org/data/definitions/536.html
- https://cwe.mitre.org/data/definitions/546.html
- https://cwe.mitre.org/data/definitions/550.html
- https://cwe.mitre.org/data/definitions/551.html
- https://cwe.mitre.org/data/definitions/552.html
- https://cwe.mitre.org/data/definitions/556.html
- https://cwe.mitre.org/data/definitions/558.html
- https://cwe.mitre.org/data/definitions/562.html
- https://cwe.mitre.org/data/definitions/563.html
- https://cwe.mitre.org/data/definitions/564.html
- https://cwe.mitre.org/data/definitions/578.html