CVE-2019-9971 Explained : Impact and Mitigation

A vulnerability in PhoneSystem Terminal within the installation of 3CX Phone System (Debian based) version 16.0.0.1570 allows unauthorized individuals to gain root privileges by exploiting the tcpdump command with sudo, without requiring a password.

Understanding CVE-2019-9971

This CVE entry describes a security issue in 3CX Phone System that enables attackers to escalate privileges through a specific command execution.

What is CVE-2019-9971?

The vulnerability in PhoneSystem Terminal of 3CX Phone System version 16.0.0.1570 allows unauthorized users to obtain root privileges by leveraging the tcpdump command with sudo, without the need for a password. This security flaw is due to the unsafe nature of the -z option (postrotate-command) of tcpdump when used in conjunction with sudo.

The Impact of CVE-2019-9971

Exploiting this vulnerability can lead to unauthorized individuals gaining root access to the affected system, potentially resulting in complete control over the device and access to sensitive information.

Technical Details of CVE-2019-9971

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability arises from the insecure handling of the -z option (postrotate-command) of tcpdump when combined with sudo, allowing unauthorized users to escalate privileges and gain root access.

Affected Systems and Versions

Product: 3CX Phone System
Version: 16.0.0.1570

Exploitation Mechanism

Unauthorized individuals can exploit this vulnerability by utilizing the tcpdump command with sudo, bypassing the need for a password and gaining root privileges on the system.

Mitigation and Prevention

To address CVE-2019-9971 and enhance system security, follow these mitigation strategies:

Immediate Steps to Take

Disable unnecessary sudo access for non-administrative users.
Monitor system logs for any suspicious activities related to the tcpdump command.
Implement strict access controls to limit the execution of privileged commands.

Long-Term Security Practices

Regularly update the 3CX Phone System to the latest version to patch known vulnerabilities.
Conduct security training for users to raise awareness about safe command execution practices.

Patching and Updates

Apply security patches provided by 3CX Phone System promptly to address the vulnerability and prevent potential exploitation.