CVE-2020-5231 Explained : Impact and Mitigation

Opencast users with the role ROLE_COURSE_ADMIN can exploit a vulnerability allowing them to create new users without the ROLE_ADMIN privilege.

Understanding CVE-2020-5231

This CVE highlights a security issue in Opencast versions prior to 7.6 and 8.1, enabling users with a specific role to create new users.

What is CVE-2020-5231?

In Opencast versions before 7.6 and 8.1, users with the ROLE_COURSE_ADMIN role can utilize the user-utils endpoint to create new users without the ROLE_ADMIN privilege. This role is not documented or referenced in the code, except in security configurations.

The Impact of CVE-2020-5231

The vulnerability has a CVSS base score of 4.8, indicating a medium severity issue. It requires high privileges and user interaction, affecting confidentiality and integrity.

Technical Details of CVE-2020-5231

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The flaw allows ROLE_COURSE_ADMIN users to create new users without the necessary ROLE_ADMIN privilege.

Affected Systems and Versions

Affected versions: < 7.6, >= 8.0, < 8.1
Product: Opencast

Exploitation Mechanism

Users with the ROLE_COURSE_ADMIN role can exploit the user-utils endpoint to create new users without the ROLE_ADMIN privilege.

Mitigation and Prevention

To address and prevent the CVE-2020-5231 vulnerability, follow these steps:

Immediate Steps to Take

Upgrade Opencast to version 7.6 or 8.1 to apply the security fix.
Review and adjust user roles and permissions to ensure proper authorization.

Long-Term Security Practices

Regularly review and update security configurations and roles.
Conduct security training to educate users on proper role usage and permissions.

Patching and Updates

Stay informed about Opencast security advisories and apply patches promptly to mitigate potential risks.