CVE-2018-10366 in Users Plugin
Summary
by MITRE
An issue was discovered in the Users (aka Front-end user management) plugin 1.4.5 for October CMS. XSS exists in the name field.
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Analysis
by VulDB Data Team • 07/28/2025
The vulnerability identified as CVE-2018-10366 represents a cross-site scripting flaw within the Users plugin version 1.4.5 of October CMS, a popular open-source content management system. This issue specifically affects the front-end user management functionality, which allows users to register, authenticate, and manage their accounts through the public-facing website interface. The vulnerability manifests in the name field of user registration forms, where insufficient input validation and output encoding create opportunities for malicious actors to inject harmful scripts into the application's response.
The technical nature of this vulnerability aligns with CWE-79, which defines Cross-Site Scripting as a weakness that occurs when an application includes untrusted data in a new web page without proper validation or encoding, or without the use of a safe rendering technique. In this case, the name field serves as the attack vector where user-supplied input containing malicious JavaScript code can be executed in the context of other users' browsers. The flaw exists because the application fails to properly sanitize or escape user-provided data before rendering it in HTML output, allowing attackers to inject script tags, event handlers, or other malicious payloads that execute when other users view the affected content.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform various malicious activities through the compromised user sessions. An attacker could craft a malicious name containing JavaScript that steals session cookies, redirects users to phishing sites, or performs actions on behalf of authenticated users. This vulnerability particularly affects the integrity and confidentiality of user data within the October CMS environment, as it allows unauthorized access to potentially sensitive information and can facilitate account takeovers. The issue is especially concerning in multi-user environments where users may have varying privilege levels, as it could enable privilege escalation or data manipulation through session hijacking techniques.
Mitigation strategies for CVE-2018-10366 should include immediate patching of the Users plugin to version 1.4.6 or later, which contains the necessary fixes for input validation and output encoding. Organizations should implement comprehensive input sanitization measures, including the use of HTML entity encoding for all user-provided data before rendering in web pages, and enforce strict validation of name field inputs to reject potentially malicious content. The principle of least privilege should be applied by ensuring that user registration and profile management features are properly secured, with additional monitoring and logging of user account modifications. Security teams should also consider implementing content security policies to prevent unauthorized script execution and deploy web application firewalls to detect and block suspicious input patterns. This vulnerability demonstrates the importance of secure coding practices and proper input validation as outlined in the OWASP Top Ten and ATT&CK framework categories related to web application security and credential access. Organizations should conduct regular security assessments and maintain updated threat intelligence to identify similar vulnerabilities in their October CMS installations and other web applications.