CVE-2023-46287 is a security vulnerability classified as a cross-site scripting (XSS) flaw affecting NagVis, an open-source visualization tool for network and system monitoring. The vulnerability is located in the select function of the share/server/core/functions/html.php file in NagVis versions before 1.9.38. XSS vulnerabilities occur when an application includes untrusted input in web pages without proper validation or escaping, allowing attackers to inject malicious scripts that execute in users' browsers. In this case, the select function improperly handles input, enabling an attacker to craft a malicious payload that, when rendered by a victim's browser, executes arbitrary JavaScript code. Such exploitation can lead to session hijacking, theft of sensitive information, or redirection to malicious sites. The vulnerability does not require authentication, increasing its risk profile, but no known exploits have been reported in the wild as of the publication date. The absence of a CVSS score suggests the need for a severity assessment based on the impact and exploitability factors. Given the nature of XSS and the affected component, the vulnerability primarily threatens confidentiality and integrity of user sessions and data. NagVis is commonly used in network operations centers and IT monitoring environments, making the vulnerability relevant to organizations relying on this tool for infrastructure visibility. The patch for this vulnerability is included in NagVis version 1.9.38, which addresses the input handling flaw in the select function. Organizations running earlier versions should prioritize upgrading to mitigate potential risks.

For European organizations, the impact of CVE-2023-46287 can be significant in environments where NagVis is deployed for monitoring critical IT infrastructure. Successful exploitation could allow attackers to execute malicious scripts in the context of legitimate users, potentially leading to session hijacking, unauthorized access to monitoring dashboards, or manipulation of displayed data. This could undermine trust in monitoring systems, delay incident response, or facilitate further attacks within the network. Although no active exploits are known, the vulnerability's presence in monitoring tools used by enterprises, service providers, and government agencies increases the risk profile. Confidentiality and integrity of monitoring data are primarily at risk, while availability impact is limited unless combined with other attack vectors. The risk is heightened in organizations with less stringent web security controls or those that allow broad access to NagVis interfaces. Given the critical role of monitoring tools in operational security, exploitation could indirectly impact business continuity and compliance with regulatory requirements such as GDPR if sensitive data is exposed or manipulated.

1. Upgrade NagVis to version 1.9.38 or later immediately to apply the official patch that fixes the XSS vulnerability in the select function. 2. Implement strict input validation and output encoding on all user-supplied data within NagVis, especially in custom configurations or extensions that interact with the select function. 3. Deploy Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing NagVis dashboards. 4. Limit access to NagVis interfaces to trusted networks and authenticated users where possible, reducing the attack surface. 5. Monitor web server and application logs for suspicious input patterns or repeated attempts to exploit XSS vectors. 6. Educate users and administrators about the risks of XSS and encourage prompt reporting of unusual behavior in monitoring dashboards. 7. Consider web application firewalls (WAF) with rules targeting XSS payloads as an additional protective layer. 8. Regularly review and update NagVis and all associated components to maintain security posture.