CVE-2021-41462 in concrete5-legacy
Summary
by MITRE • 10/02/2021
Cross-site scripting (XSS) vulnerability in concrete/elements/collection_add.php in concrete5-legacy 5.6.4.0 and below allows remote attackers to inject arbitrary web script or HTML via the ctID parameter.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 10/08/2021
The CVE-2021-41462 vulnerability represents a critical cross-site scripting flaw within the concrete5-legacy content management system version 5.6.4.0 and earlier releases. This vulnerability exists in the collection_add.php file located within the concrete/elements/collection_add.php path, making it a prime target for malicious actors seeking to exploit web application security weaknesses. The flaw specifically manifests when the application fails to properly sanitize or validate the ctID parameter, which is used to identify collection types during content creation processes. This vulnerability falls under the CWE-79 category of Cross-Site Scripting, which is classified as a fundamental web application security weakness that allows attackers to inject malicious client-side scripts into web pages viewed by other users.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding practices within the concrete5 legacy codebase. When an attacker submits a malicious ctID parameter value containing script tags or other malicious payloads, the application processes this input without adequate sanitization mechanisms. The vulnerability occurs because the system does not properly escape or filter user-supplied data before rendering it within the web page context, creating an environment where attacker-controlled scripts can execute in the browser of unsuspecting users. This weakness is particularly dangerous because it operates at the user interface level where legitimate users interact with content management functionality, making it difficult to distinguish between legitimate and malicious inputs.
The operational impact of CVE-2021-41462 extends beyond simple data theft or defacement, as it can enable sophisticated attack chains that leverage the compromised system for further exploitation. Attackers can use this vulnerability to execute malicious scripts that steal session cookies, redirect users to phishing sites, or perform actions on behalf of authenticated users without their knowledge. The attack surface is particularly concerning for content management systems since they often handle sensitive data and user credentials, making this vulnerability a potential gateway for more severe attacks. According to ATT&CK framework, this vulnerability maps to T1566.001 (Phishing) and T1059.001 (Command and Scripting Interpreter) techniques, as it enables both user deception and code execution capabilities. The vulnerability affects all users who have access to the content management interface, making it particularly dangerous in multi-user environments where administrative privileges may be compromised.
Mitigation strategies for CVE-2021-41462 must address both immediate remediation and long-term architectural improvements. Organizations should prioritize upgrading to concrete5-legacy versions that have patched this vulnerability, as the original version is no longer supported and likely contains additional unpatched security flaws. Immediate patching should include implementing proper input validation and output encoding mechanisms that sanitize all user-supplied parameters before processing. The fix should enforce strict parameter validation for the ctID field, ensuring that only legitimate collection type identifiers are accepted and that any potentially malicious content is properly escaped or filtered. Security measures should also include implementing Content Security Policy headers to limit script execution capabilities and monitoring for anomalous parameter usage patterns. Organizations should conduct thorough security testing of their web applications to identify similar vulnerabilities in other components that may have been overlooked, as legacy systems often contain multiple interconnected security weaknesses that compound the overall risk profile.