Privilege escalation in systemd

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU17120

Risk: Low

CVSSv3.1: 7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2018-16888

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a local attacker to escalate privileges on the system.

The vulnerability exists due to incorrect check the content of PIDFile files before using it to kill processes. A local attacker can who is able to write to the PIDFile of the mentioned service can trick systemd into killing other services and/or privileged processes.

Mitigation

Update to version 237.

Vulnerable software versions

systemd: 174 - 235

External links

http://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16888
http://github.com/systemd/systemd/pull/7816

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.