CVE-2021-25931 Explained : Impact and Mitigation

OpenNMS Horizon and OpenNMS Meridian are affected by a CSRF vulnerability that allows an attacker to assign administrator privileges to a normal user. By exploiting the lack of CSRF protection at

/opennms/admin/userGroupView/users/updateUser

, an attacker can manipulate the admin user to elevate a normal user's permissions.

Understanding CVE-2021-25931

This CVE identifies a vulnerability in OpenNMS Horizon and OpenNMS Meridian that enables Cross-Site Request Forgery attacks.

What is CVE-2021-25931?

In OpenNMS Horizon and OpenNMS Meridian, the absence of CSRF protection at a specific endpoint permits attackers to deceive admin users into granting administrator rights to regular users.

The Impact of CVE-2021-25931

The vulnerability allows threat actors to conduct CSRF attacks, tricking admin users into unintentionally elevating user privileges.

Technical Details of CVE-2021-25931

This section provides deeper insight into the vulnerability.

Vulnerability Description

OpenNMS Horizon and OpenNMS Meridian versions opennms-1-0-stable through opennms-27.1.0-1, meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1, and meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1 are susceptible to CSRF due to a lack of protection at the mentioned endpoint.

Affected Systems and Versions

The affected versions include opennms-1-0-stable through opennms-27.1.0-1 and meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1, meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.6-1.

Exploitation Mechanism

Attackers can exploit this vulnerability by crafting malicious websites to deceive admin users to unintentionally escalate user privileges.

Mitigation and Prevention

To protect systems from this vulnerability, follow the below mitigation steps.

Immediate Steps to Take

Ensure the CSRF protection mechanisms are implemented, and users are cautious while interacting with external websites.

Long-Term Security Practices

Regular security assessments, user awareness training, and keeping systems up to date can enhance overall security posture.

Patching and Updates

Apply the latest patches provided by OpenNMS to fix the CSRF vulnerability and prevent unauthorized privilege escalation.