CVE-2018-14686 in XYCMS
Summary
by MITRE
system/edit_book.php in XYCMS 1.7 has stored XSS via a crafted add_do.php request, related to add_book.php.
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Analysis
by VulDB Data Team • 03/11/2020
The vulnerability identified as CVE-2018-14686 represents a critical stored cross-site scripting flaw within XYCMS version 1.7, specifically affecting the system/edit_book.php component. This security weakness arises from inadequate input validation and sanitization mechanisms that fail to properly process user-supplied data before storing it within the application's database. The vulnerability is triggered through a malicious request to add_do.php which subsequently influences the add_book.php interface, creating a persistent XSS vector that can affect multiple users who interact with the compromised content.
The technical exploitation of this vulnerability occurs when an attacker crafts a malicious payload and submits it through the add_do.php endpoint, which then gets stored in the system's database and subsequently rendered in the edit_book.php interface without proper sanitization. This stored nature of the vulnerability means that the malicious script persists in the application's data store and executes every time a user accesses the affected page, making it particularly dangerous for web applications that handle user-generated content. The flaw demonstrates poor security practices in data handling and input validation, creating an environment where malicious scripts can be injected and executed in the context of other users' browsers.
The operational impact of this vulnerability extends beyond simple data theft or defacement, as it provides attackers with the capability to execute arbitrary JavaScript code in victims' browsers, potentially leading to session hijacking, credential theft, or redirection to malicious sites. Users who view the compromised content are unknowingly exposed to the attacker's payload, making this a significant threat to the application's security posture and user trust. The vulnerability affects the core content management functionality of XYCMS, potentially compromising all user accounts and data within the application's scope. This type of vulnerability directly violates security principles outlined in the OWASP Top Ten and represents a classic example of inadequate output encoding and input validation practices.
Mitigation strategies for CVE-2018-14686 should focus on implementing comprehensive input validation and output encoding mechanisms throughout the application's data flow. The most effective remediation involves sanitizing all user-supplied input before storage and properly encoding all output before rendering, particularly when dealing with HTML content. Organizations should implement Content Security Policy headers to limit the execution of unauthorized scripts and ensure that all user inputs are validated against strict whitelists of acceptable characters and formats. Additionally, the application should employ proper escape sequences when rendering user-generated content, and regular security audits should be conducted to identify similar vulnerabilities in the codebase. This vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws, and maps to ATT&CK technique T1566 which covers social engineering tactics involving malicious content delivery. The remediation efforts should also include updating to the latest version of XYCMS where this vulnerability has been patched, as well as implementing proper security training for developers to prevent similar issues in future development cycles.