CVE-2016-2058 in Xymon
Summary
by MITRE
Multiple cross-site scripting (XSS) vulnerabilities in Xymon 4.1.x, 4.2.x, and 4.3.x before 4.3.25 allow (1) remote Xymon clients to inject arbitrary web script or HTML via a status-message, which is not properly handled in the "detailed status" page, or (2) remote authenticated users to inject arbitrary web script or HTML via an acknowledgement message, which is not properly handled in the "status" page.
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Analysis
by VulDB Data Team • 07/24/2022
The CVE-2016-2058 vulnerability represents a critical cross-site scripting flaw affecting Xymon monitoring software versions 4.1.x through 4.3.x prior to 4.3.25. This vulnerability manifests in two distinct attack vectors that exploit improper input sanitization within the web interface components of the monitoring system. The primary security concern arises from the lack of proper validation and sanitization of user-supplied data in the status message handling mechanisms, creating opportunities for malicious actors to inject arbitrary web scripts or HTML content that can be executed in the context of other users' browsers. The vulnerability impacts both unauthenticated remote clients and authenticated users, significantly expanding the potential attack surface and threat model.
The technical implementation of this vulnerability stems from inadequate input validation within the Xymon web application's status display functionality. When status messages or acknowledgment messages are processed and rendered on the detailed status page or standard status page respectively, the application fails to properly sanitize user input before incorporating it into the web response. This allows attackers to craft malicious payloads that, when displayed to other users, execute in their browser context. The vulnerability is particularly dangerous because it operates at the application layer, leveraging the trust relationship between legitimate users and the monitoring system to deliver malicious code. This flaw directly maps to CWE-79 which defines Cross-Site Scripting as a weakness where untrusted data is processed and included in web pages without proper validation or encoding.
The operational impact of CVE-2016-2058 extends beyond simple script execution, as it can enable sophisticated attack chains that compromise the integrity of the monitoring infrastructure. Remote attackers can manipulate status messages to inject malicious JavaScript that could redirect users to phishing sites, steal session cookies, or even establish persistent backdoors through the monitoring interface. Authenticated users who receive malicious acknowledgment messages could inadvertently trigger script execution that compromises their browser sessions and potentially provides attackers with elevated privileges within the monitoring system. This vulnerability undermines the fundamental security assumptions of the Xymon monitoring platform, as it allows attackers to exploit the very functionality designed to provide system visibility and alerting. The attack can be executed through various means including manipulating client status updates or through the system's acknowledgment mechanisms, making it particularly difficult to defend against through traditional network-based security controls.
Mitigation strategies for CVE-2016-2058 should prioritize immediate patching of affected Xymon installations to version 4.3.25 or later, which contains the necessary input validation fixes. Organizations should implement comprehensive input sanitization at multiple layers, including the application firewall, web application firewall, and application code level. Network segmentation and access controls should limit exposure of the monitoring system to untrusted networks and users. Security monitoring should be enhanced to detect suspicious status message patterns or unexpected script execution in the monitoring interface. Regular security assessments should be conducted to verify proper implementation of input validation and output encoding mechanisms. Additionally, security awareness training should be provided to administrators to recognize potential signs of XSS exploitation attempts, and incident response procedures should be updated to address potential XSS-based compromises of monitoring systems. The vulnerability's classification under the ATT&CK framework would include techniques such as T1059.007 for script execution and T1566 for credential access through social engineering via compromised monitoring interfaces.