CVE-2026-31803 in iTop
Summary
by MITRE • 08/22/2026
Combodo iTop is a web based IT service management tool. Prior to 3.2.3, 3.2.3, there is a Reflected Cross-Site Scripting (XSS) vulnerability in pages/tagadmin.php. This issue has been fixed in version 3.2.3.
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Analysis
by VulDB Data Team • 08/22/2026
The vulnerability identified within Combodo iTop versions prior to and including 3.2.3 represents a classic instance of Reflected Cross-Site Scripting, specifically located in the tag administration interface at pages/tagadmin.php. As an IT service management platform, iTip handles significant amounts of organizational data and user interactions through its web-based interface. The specific flaw arises from insufficient input validation or sanitization mechanisms applied to parameters passed via HTTP requests within this administrative module. When a malicious actor crafts a URL containing specially constructed script payloads embedded in query parameters or form fields associated with tag management, the application processes these inputs without adequate neutralization of executable content. Consequently, when the server generates the response page reflecting user input back into the HTML body, the injected scripts are executed by the victim's web browser within the context of the iTop session.
This technical flaw aligns directly with Common Weakness Enumeration identifier CWE-79, which describes Improper Neutralization of Input During Web Page Generation known as Cross-site Scripting. The attack vector is classified under MITRE ATT&CK technique T1059.007, specifically Command and Scripting Interpreter via Browser or User Interface interactions. Because the vulnerability is reflected rather than stored, it requires social engineering to be effective. An attacker must lure a privileged user, such as an administrator responsible for managing tags within the ITSM environment, into clicking a malicious link. The payload does not persist in the database but is instead executed immediately upon page load, leveraging the trust that users place in their organization's internal tools and the administrative privileges associated with those accounts.
The operational impact of this vulnerability extends beyond simple script execution to potential compromise of sensitive IT service management operations. Since tagadmin.php likely operates within an authenticated session with elevated permissions, successful exploitation allows attackers to perform actions on behalf of the victim user. This can include stealing session cookies or authentication tokens through JavaScript that exfiltrates data to a remote server controlled by the attacker. Furthermore, it enables phishing attacks where fake login forms are injected into the legitimate interface to harvest credentials for other systems integrated with iTop. In environments where iTop manages critical infrastructure configurations, this could lead to unauthorized modifications of service catalogs or incident tracking workflows if combined with additional vulnerabilities such as Cross-Site Request Forgery weaknesses in related endpoints.
Mitigation strategies focus primarily on upgrading the software environment immediately. Organizations running Combodo iTop versions earlier than 3.2.3 must apply the vendor-provided patch that addresses this specific input validation gap. The fix typically involves implementing strict output encoding and context-aware sanitization for all user-supplied data rendered in HTML contexts, ensuring that special characters are converted to their corresponding HTML entities before display. Additionally, security administrators should enforce Content Security Policy headers where feasible to restrict the execution of inline scripts, thereby providing a defense-in-depth layer even if input validation is bypassed. Regular vulnerability scanning and code review processes for custom modules within iTop can further reduce the risk surface by identifying similar patterns in other administrative pages before they are exploited in production environments.