CVE-2019-16990 : What You Need to Know

FusionPBX version 4.5.7 and earlier are vulnerable to a path traversal issue due to improper sanitization of the 'file' variable in the music_on_hold.php file. This allows attackers to download any file using a base64 encoded pathname.

Understanding CVE-2019-16990

This CVE identifies a security vulnerability in FusionPBX versions up to 4.5.7 that can be exploited through a path traversal attack.

What is CVE-2019-16990?

The vulnerability arises from the lack of proper sanitization of user-supplied input, specifically the 'file' variable, which can be manipulated to access unauthorized files.

The Impact of CVE-2019-16990

The vulnerability could lead to unauthorized access to sensitive files on the server, potentially exposing confidential information or allowing attackers to compromise the system.

Technical Details of CVE-2019-16990

FusionPBX's music_on_hold.php file is the focal point of this vulnerability.

Vulnerability Description

The 'file' variable in music_on_hold.php is not sanitized, enabling attackers to download any file by manipulating the base64 encoded pathname.

Affected Systems and Versions

FusionPBX versions up to 4.5.7

Exploitation Mechanism

Attackers can exploit this vulnerability by manipulating the 'file' variable in the URL to access and download arbitrary files on the server.

Mitigation and Prevention

It is crucial to take immediate steps to secure systems and prevent exploitation.

Immediate Steps to Take

Apply the patch provided by FusionPBX to fix the vulnerability.
Regularly monitor and review access logs for any suspicious activities.

Long-Term Security Practices

Implement input validation and sanitization mechanisms in web applications to prevent similar vulnerabilities.
Conduct regular security assessments and penetration testing to identify and address potential weaknesses.

Patching and Updates

Update FusionPBX to the latest version that includes the patch for CVE-2019-16990 to mitigate the risk of exploitation.