CVE-2017-16866 in FineCMS
Summary
by MITRE
dayrui FineCms 5.2.0 before 2017.11.16 has Cross Site Scripting (XSS) in core/M_Controller.php via the DR_URI field.
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Analysis
by VulDB Data Team • 01/10/2023
The vulnerability identified as CVE-2017-16866 affects dayrui FineCms version 5.2.0 and earlier, specifically before the patch release of November 16, 2017. This issue manifests as a cross site scripting vulnerability within the core/M_Controller.php file, which processes the DR_URI field. The vulnerability represents a classic injection flaw that allows malicious actors to execute arbitrary JavaScript code within the context of a victim's browser session. The DR_URI field serves as an entry point for user-supplied input that is not properly sanitized or validated before being rendered in the application's output. This particular weakness falls under the CWE-79 category of Cross Site Scripting, which is one of the most prevalent and dangerous web application vulnerabilities according to the CWE database. The vulnerability demonstrates poor input validation practices where the application fails to adequately escape or filter user-controllable data before incorporating it into dynamic web content.
The technical exploitation of this vulnerability occurs when an attacker crafts malicious input containing script code within the DR_URI parameter and submits it to the vulnerable FineCms application. When the application processes this input and renders it without proper sanitization, the embedded JavaScript executes in the browser of any user who views the affected page or interacts with the vulnerable functionality. The attack vector is particularly concerning because it can be delivered through various means including crafted URLs, form submissions, or even via API endpoints that accept URI parameters. The vulnerability's impact extends beyond simple script execution as it can enable session hijacking, credential theft, defacement of web pages, and redirection to malicious sites. The XSS flaw operates at the application layer and can be classified under the ATT&CK technique T1059.007 for Scripting, specifically targeting the web application environment where the vulnerability exists. This allows attackers to potentially establish persistent access to user sessions and escalate privileges within the application context.
The operational impact of CVE-2017-16866 is significant for organizations utilizing vulnerable FineCms installations, as it provides attackers with a means to compromise user sessions and potentially gain unauthorized access to sensitive data. The vulnerability can be exploited to steal cookies, session tokens, and other authentication credentials, leading to full account compromise. Additionally, the XSS payload could be designed to redirect users to phishing sites or inject malicious content that modifies the application's behavior. The affected M_Controller.php file suggests this vulnerability impacts core application functionality, potentially affecting multiple modules or features that rely on URI processing. Organizations may experience reputational damage, data breaches, and regulatory compliance issues if this vulnerability is exploited successfully. The vulnerability's persistence stems from the fact that it exists in the core application logic rather than being isolated to a specific module, making it more difficult to patch and more impactful when exploited. Security teams should consider this vulnerability as a high-priority issue requiring immediate remediation to protect against potential exploitation by threat actors.
Mitigation strategies for CVE-2017-16866 should focus on implementing proper input validation and output encoding mechanisms to prevent malicious script code from being executed. The primary fix involves updating to FineCms version 5.2.0 or later that includes the patch for this vulnerability. Organizations should also implement Content Security Policy headers to limit script execution and reduce the impact of potential XSS attacks. Input sanitization techniques including proper HTML escaping, whitelist validation, and parameterized queries should be implemented throughout the application to prevent similar vulnerabilities. Security monitoring should include detection of suspicious URI patterns and unusual parameter values that might indicate exploitation attempts. The vulnerability highlights the importance of secure coding practices and regular security assessments, particularly for web applications that process user input. Organizations should also consider implementing web application firewalls to detect and block malicious URI parameters. Regular security updates and patch management processes are essential to prevent exploitation of known vulnerabilities like CVE-2017-16866, which can be addressed through automated patching solutions or manual update procedures. The vulnerability serves as a reminder of the critical need for input validation at all levels of application development and the importance of following secure coding guidelines to prevent XSS attacks.