CVE-2023-4187 in icms2
Summary
by MITRE • 08/05/2023
Cross-site Scripting (XSS) - Stored in GitHub repository instantsoft/icms2 prior to 2.16.1-git.
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Analysis
by VulDB Data Team • 07/13/2026
Cross-site scripting vulnerabilities represent one of the most prevalent and dangerous web application security flaws, with stored XSS variants posing particular risks due to their persistent nature and potential for widespread impact. The vulnerability identified in the GitHub repository instantsoft/icms2 prior to version 2.16.1-git demonstrates a classic stored cross-site scripting flaw that allows attackers to inject malicious scripts into web applications where these scripts are subsequently executed against other users who access the affected content. This particular vulnerability resides within the content management system's handling of user-submitted data, specifically in areas where input validation and output encoding mechanisms fail to properly sanitize or escape potentially malicious content.
The technical implementation of this stored XSS vulnerability occurs when user-provided data is accepted through forms, comments, or other input mechanisms without adequate sanitization processes. When such data is later displayed on web pages without proper HTML escaping or context-appropriate encoding, malicious scripts can be executed within the browser context of unsuspecting users who view the affected content. The flaw typically manifests in parameters or fields that handle rich text content, user-generated comments, or administrative input where the application fails to implement proper security controls such as input validation, output encoding, or Content Security Policy headers. According to CWE classification, this vulnerability maps directly to CWE-79 which describes improper neutralization of input during web page generation, making it a fundamental weakness in web application security architecture.
The operational impact of this stored XSS vulnerability extends beyond simple data theft or session hijacking, as it can enable attackers to perform actions on behalf of victims with the privileges of those users. An attacker could potentially inject scripts that steal authentication tokens, redirect users to malicious sites, modify content displayed on the website, or even execute arbitrary commands if the application's security model is sufficiently weak. The persistent nature of stored XSS means that once the malicious payload is injected and saved within the application's database, it will automatically execute each time affected users view the compromised content, making it particularly dangerous for applications with active user communities. This vulnerability type directly aligns with ATT&CK technique T1531 which focuses on "Use of Web Shell" and represents a significant threat vector in the context of web application penetration testing.
Mitigation strategies for this stored XSS vulnerability must address both immediate remediation and long-term architectural improvements to prevent similar issues from arising. The most effective immediate solution involves implementing comprehensive input validation and output encoding mechanisms throughout the application, ensuring that all user-provided data is sanitized before storage and properly escaped before display. This includes implementing proper HTML escaping for different contexts such as HTML content, JavaScript contexts, and URL parameters. Organizations should also implement Content Security Policy headers to limit script execution capabilities, employ proper input validation using allowlists rather than blocklists, and ensure that all user-generated content undergoes rigorous sanitization processes. Additionally, regular security testing including automated vulnerability scanning and manual penetration testing should be conducted to identify potential XSS vulnerabilities before they can be exploited in production environments. The implementation of secure coding practices and developer security training can significantly reduce the likelihood of such vulnerabilities being introduced during application development cycles, aligning with industry best practices established by organizations such as OWASP and NIST cybersecurity frameworks.