CVE-2021-25935 : What You Need to Know

OpenNMS Horizon and OpenNMS Meridian are prone to Stored Cross-Site Scripting vulnerability, allowing attackers to inject and store malicious scripts due to improper validation checks.

Understanding CVE-2021-25935

This CVE involves a Stored Cross-Site Scripting vulnerability in OpenNMS Horizon and OpenNMS Meridian versions mentioned in the descriptions.

What is CVE-2021-25935?

CVE-2021-25935 is a Stored Cross-Site Scripting vulnerability in OpenNMS Horizon and OpenNMS Meridian that could be exploited by attackers to inject arbitrary scripts into the database.

The Impact of CVE-2021-25935

This vulnerability allows attackers to bypass regex validation, leading to the execution of malicious scripts that can compromise the security and integrity of the affected systems.

Technical Details of CVE-2021-25935

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The flaw exists in the

add()

function of OpenNMS, where improper validation checks on the

foreign-source

parameter allow malicious script injections.

Affected Systems and Versions

OpenNMS Horizon versions opennms-17.0.0-1 through opennms-27.1.0-1 are affected, along with OpenNMS Meridian versions meridian-foundation-2015.1.0-1 through meridian-foundation-2019.1.18-1 and meridian-foundation-2020.1.0-1 through meridian-foundation-2020.1.7-1.

Exploitation Mechanism

Attackers exploit this vulnerability by sending crafted input to the

foreign-source

parameter, bypassing regex validation and storing malicious scripts in the database.

Mitigation and Prevention

To protect systems from CVE-2021-25935, immediate actions and long-term security practices should be implemented.

Immediate Steps to Take

Apply the latest security patches provided by OpenNMS to mitigate the vulnerability.
Regularly monitor for any unusual activities that might indicate an exploitation attempt.

Long-Term Security Practices

Implement input validation mechanisms to prevent malicious inputs.
Conduct regular security audits and penetration testing to identify and address vulnerabilities.

Patching and Updates

Keep systems up to date with the latest security patches and updates from OpenNMS to address known vulnerabilities.