CVE-2016-15053 in Nagios
Summary
by MITRE • 10/31/2025
Nagios XI versions prior to 5.2.4 are vulnerable to cross-site scripting (XSS) via the “My Reports” listing of the web interface. Insufficient validation or escaping of user-supplied input may allow an attacker to inject and execute arbitrary script in the context of a victim's browser.
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Analysis
by VulDB Data Team • 11/17/2025
Nagios XI version 5.2.4 and earlier contains a critical cross-site scripting vulnerability that affects the web-based reporting interface. This vulnerability exists within the "My Reports" functionality where the application fails to properly validate or sanitize user-supplied input before rendering it in the web interface. The flaw allows an attacker to inject malicious script code that executes in the context of a victim's browser session, potentially compromising user security and system integrity.
The technical nature of this vulnerability stems from inadequate input validation mechanisms within the web application's user interface components. When users navigate to the My Reports section, the application processes user-generated content without proper sanitization or encoding of special characters that could be interpreted as executable script code. This weakness directly maps to CWE-79, which identifies improper neutralization of input during web page generation as a primary cause of cross-site scripting vulnerabilities. The vulnerability occurs because the application does not implement proper output encoding or input filtering mechanisms that would prevent malicious payloads from being executed.
The operational impact of this vulnerability extends beyond simple script injection as it creates potential attack vectors for more sophisticated exploitation techniques. An attacker could craft malicious payloads that steal session cookies, redirect users to phishing sites, or execute unauthorized commands within the victim's browser context. This vulnerability particularly affects administrators and users who regularly access the reporting interface, as they may be exposed to persistent XSS attacks that could lead to complete compromise of their Nagios XI sessions. The attack surface is further expanded because the vulnerability affects the web interface itself rather than requiring privileged access to the underlying system.
Mitigation strategies should focus on immediate patching of the affected Nagios XI versions to 5.2.4 or later where the XSS vulnerability has been addressed. Organizations should implement proper input validation and output encoding mechanisms throughout the web application to prevent similar vulnerabilities from occurring in other components. Network administrators should also consider implementing additional security controls such as web application firewalls and content security policies that can help detect and prevent XSS attacks. The vulnerability aligns with ATT&CK technique T1059.007 which describes the use of script-based attacks, and organizations should monitor for suspicious activity patterns that might indicate exploitation attempts. Regular security assessments and penetration testing should be conducted to identify potential input validation gaps in web applications and ensure that proper security controls are in place to prevent unauthorized script execution within user browser contexts.