CVE-2018-6518 in Composr
Summary
by MITRE
Composr CMS 10.0.13 has XSS via the site_name parameter in a page=admin-setupwizard&type=step3 request to /adminzone/index.php.
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Analysis
by VulDB Data Team • 03/07/2023
Composr CMS version 10.0.13 contains a cross-site scripting vulnerability that allows remote attackers to inject malicious scripts into web pages viewed by other users. This vulnerability specifically affects the administrative setup wizard functionality where the site_name parameter is processed without proper input validation or output encoding. The vulnerability exists within the page=admin-setupwizard&type=step3 request handler in the adminzone/index.php file, making it accessible during the initial configuration phase of the content management system. The flaw represents a classic stored cross-site scripting vulnerability where user-supplied input flows directly into the HTML output without adequate sanitization measures.
The technical implementation of this vulnerability stems from insufficient input validation mechanisms within the Composr CMS administrative interface. When administrators or users interact with the setup wizard, the site_name parameter is accepted and processed without proper sanitization of special characters that could be interpreted as HTML or JavaScript code. This allows an attacker to inject malicious payloads that execute in the context of other users' browsers when they view pages containing the vulnerable parameter. The vulnerability is particularly concerning because it occurs during the initial setup phase, potentially allowing attackers to compromise the system before proper security measures are fully implemented. The attack vector requires no authentication and can be exploited through a simple HTTP request containing malicious script code within the site_name parameter.
The operational impact of this vulnerability extends beyond simple script injection, as it can enable attackers to perform various malicious activities including session hijacking, credential theft, and redirection to malicious websites. An attacker could craft a payload that steals administrator cookies or session tokens, effectively granting them full administrative access to the compromised system. The vulnerability also enables phishing attacks where users are redirected to fraudulent sites that appear legitimate. Given that this affects the setup wizard functionality, it could be exploited during the initial deployment of the CMS, potentially compromising systems before they are properly secured. The vulnerability aligns with CWE-79 which categorizes cross-site scripting flaws, and maps to attack techniques in the MITRE ATT&CK framework under T1059.007 for scripting and T1566 for spearphishing with a malicious attachment.
Mitigation strategies for this vulnerability should include immediate implementation of input validation and output encoding mechanisms within the CMS codebase. The site_name parameter must be sanitized to remove or encode potentially dangerous characters such as angle brackets, quotes, and script tags before being rendered in HTML output. Organizations should also implement proper content security policies and input validation routines that prevent the execution of unauthorized scripts. Additionally, administrators should be advised to avoid using the setup wizard in production environments and to ensure that all input fields are properly sanitized before being processed. The vulnerability highlights the importance of secure coding practices and input validation, particularly in administrative interfaces where privileged operations occur. Regular security updates and patch management should be implemented to address similar vulnerabilities in the CMS platform. Organizations should also consider implementing web application firewalls to detect and block malicious requests containing known XSS patterns. The fix should involve comprehensive testing of all parameters passed through administrative interfaces to ensure that no similar vulnerabilities exist in other parts of the application.