CVE-2021-31540 : What You Need to Know

Wowza Streaming Engine through 4.8.5 (in a default installation) has incorrect file permissions of configuration files in the conf/ directory. A regular local user is able to read and write to all the configuration files, e.g., modify the application server configuration.

Understanding CVE-2021-31540

This CVE highlights a vulnerability in Wowza Streaming Engine that allows a local user to manipulate configuration files due to incorrect file permissions.

What is CVE-2021-31540?

CVE-2021-31540 affects Wowza Streaming Engine versions up to 4.8.5 in default installations. It enables unauthorized users to access and alter critical configuration files, posing a significant security risk.

The Impact of CVE-2021-31540

The vulnerability grants unauthorized access to local users, leaving the infrastructure exposed to potential attacks. Attackers can modify application server configurations, leading to system compromise and data breaches.

Technical Details of CVE-2021-31540

The technical details of CVE-2021-31540 include vulnerability description, affected systems and versions, and the exploitation mechanism.

Vulnerability Description

The security flaw arises from incorrect file permissions on configuration files within the conf/ directory, allowing unauthorized users to read, write, and modify sensitive settings.

Affected Systems and Versions

Wowza Streaming Engine versions up to 4.8.5 in default installations are impacted by this vulnerability.

Exploitation Mechanism

By leveraging the incorrect file permissions, a local user can exploit the vulnerability to gain unauthorized access to critical configuration files and make unauthorized modifications.

Mitigation and Prevention

To secure systems against CVE-2021-31540, immediate steps and long-term security practices should be implemented, including regular patching and updates.

Immediate Steps to Take

Immediately review and adjust file permissions on configuration files to restrict unauthorized access. Regularly monitor for any unauthorized changes or access.

Long-Term Security Practices

Implement the principle of least privilege, enforce strong authentication mechanisms, and conduct regular security audits to prevent unauthorized access and modifications.

Patching and Updates

Ensure all Wowza Streaming Engine instances are updated to version 4.8.12 or later to address the vulnerability and enhance system security.