CVE-2018-16888 : Security Advisory and Response

A vulnerability in systemd versions prior to v237 allows a local attacker to deceive systemd into terminating other services and privileged processes by exploiting PIDFile files.

Understanding CVE-2018-16888

This CVE involves a weakness in systemd that can be exploited by a malicious local attacker to terminate processes.

What is CVE-2018-16888?

The vulnerability in systemd allows attackers with write access to PIDFile to trick systemd into terminating other services and privileged processes.

The Impact of CVE-2018-16888

The vulnerability has a CVSS base score of 4.4 (Medium severity) with high availability impact. It requires low privileges but user interaction is required for exploitation.

Technical Details of CVE-2018-16888

This section provides detailed technical information about the vulnerability.

Vulnerability Description

Systemd does not adequately validate PIDFile files before using them to terminate processes, enabling attackers to deceive systemd into killing other services and privileged processes.

Affected Systems and Versions

Affected Product: systemd
Vendor: The systemd Project
Vulnerable Version: v237 and earlier

Exploitation Mechanism

Attack Complexity: High
Attack Vector: Local
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Availability Impact: High
Confidentiality Impact: None
Integrity Impact: None

Mitigation and Prevention

Steps to address and prevent the exploitation of CVE-2018-16888.

Immediate Steps to Take

Update systemd to version v237 or later to mitigate the vulnerability.
Monitor PIDFile permissions to prevent unauthorized write access.

Long-Term Security Practices

Implement the principle of least privilege to restrict access to critical files.
Regularly review and update systemd configurations to enhance security.

Patching and Updates

Apply patches provided by the vendor to address the vulnerability.