CVE-2017-2285 in Simple Custom CSS
Summary
by MITRE
Cross-site scripting vulnerability in Simple Custom CSS and JS prior to version 3.4 allows remote attackers to inject arbitrary web script or HTML via unspecified vectors.
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Analysis
by VulDB Data Team • 05/06/2025
The vulnerability identified as CVE-2017-2285 represents a cross-site scripting flaw within the Simple Custom CSS and JS WordPress plugin, affecting versions prior to 3.4. This type of vulnerability falls under the CWE-79 category, which specifically addresses cross-site scripting attacks where malicious scripts are injected into otherwise trusted websites. The vulnerability exists in the plugin's handling of user input without proper sanitization or validation mechanisms, creating an entry point for remote attackers to execute arbitrary web scripts or HTML code within the context of users' browsers.
The technical implementation of this vulnerability stems from inadequate input validation and output encoding practices within the plugin's codebase. Attackers can exploit this weakness by crafting malicious input that gets processed and rendered on the target website without proper sanitization. The unspecified vectors suggest that multiple entry points within the plugin's functionality could be compromised, potentially including custom CSS or JavaScript fields, admin interfaces, or any other user-controllable input areas where the plugin processes external data. This lack of specificity in the vector description indicates a broad attack surface that could be leveraged through various attack paths.
The operational impact of this vulnerability is significant as it enables remote code execution within the browser context of authenticated users. When exploited, attackers can manipulate the website's functionality to redirect users to malicious sites, steal session cookies, perform unauthorized actions on behalf of users, or even install malware on visiting browsers. The vulnerability particularly affects WordPress environments where the Simple Custom CSS and JS plugin is installed, potentially compromising entire websites and their user bases. This risk is compounded by the fact that the plugin is commonly used for customizing website appearance and functionality, making it a frequent target for exploitation.
Mitigation strategies for CVE-2017-2285 primarily involve immediate plugin updates to version 3.4 or later, which contain the necessary patches to address the XSS vulnerabilities. System administrators should also implement additional security measures including input validation, output encoding, and regular security audits of installed plugins. The vulnerability aligns with ATT&CK technique T1566 which covers social engineering through malicious content delivery, and T1059 which involves execution through command and scripting interpreters. Organizations should conduct thorough vulnerability assessments and ensure all WordPress installations maintain current plugin versions to prevent exploitation. Additionally, implementing web application firewalls and content security policies can provide additional layers of protection against such attacks.