CVE-2020-10819 in Nagios XI
Summary
by MITRE
Nagios XI 5.6.11 allows XSS via the includes/components/ldap_ad_integration/ username parameter.
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Analysis
by VulDB Data Team • 05/11/2025
The vulnerability identified as CVE-2020-10819 represents a cross-site scripting flaw within Nagios XI version 5.6.11 that specifically affects the ldap_ad_integration component. This issue arises from insufficient input validation and output encoding mechanisms within the web application's user interface. The vulnerability is particularly concerning as it targets the username parameter within the ldap_ad_integration includes path, making it accessible through web-based attack vectors that can be exploited by remote unauthenticated attackers.
The technical implementation of this vulnerability stems from the application's failure to properly sanitize user-supplied input before rendering it within the web page context. When a user submits a username parameter through the ldap_ad_integration interface, the system does not adequately filter or encode special characters that could be interpreted as HTML or JavaScript code. This lack of proper input validation creates an environment where malicious actors can inject arbitrary script code that executes in the context of other users' browsers. The vulnerability maps directly to CWE-79 which defines Cross-Site Scripting as a weakness where web applications fail to properly validate or encode user input before including it in dynamically generated web pages.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform various malicious activities including session hijacking, credential theft, and data exfiltration. An attacker could craft a malicious username parameter that, when processed by the vulnerable Nagios XI system, would execute JavaScript code in the victim's browser. This could lead to unauthorized access to monitoring data, potential privilege escalation within the Nagios environment, or the redirection of users to malicious sites. The attack surface is particularly wide given that Nagios XI is commonly used for critical infrastructure monitoring, making it an attractive target for cyber adversaries seeking to disrupt operations or gain unauthorized access to sensitive network information.
Security professionals should consider this vulnerability in the context of the MITRE ATT&CK framework where it relates to techniques such as T1059.007 for command and scripting interpreter and T1566 for credential access through social engineering. The vulnerability also aligns with the broader category of web application security flaws that require comprehensive mitigation strategies. Organizations should implement immediate patching procedures to address this vulnerability, as the affected Nagios XI version 5.6.11 has received updates that properly sanitize input parameters. Additionally, network segmentation and web application firewalls can provide additional layers of protection while waiting for official patches. The remediation process should include thorough input validation testing, output encoding verification, and comprehensive security scanning of the affected system to ensure no other similar vulnerabilities exist within the application's codebase.