CVE-2019-17606 in hexo-admin Plugin
Summary
by MITRE
The Post editor functionality in the hexo-admin plugin versions 2.3.0 and earlier for Node.js is vulnerable to stored XSS via the content of a post.
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Analysis
by VulDB Data Team • 10/24/2019
The vulnerability identified as CVE-2019-17606 affects the hexo-admin plugin version 2.3.0 and earlier, specifically targeting the post editor functionality within Node.js environments. This represents a critical security flaw that allows attackers to inject malicious scripts into blog posts through the administrative interface. The vulnerability stems from insufficient input validation and output sanitization mechanisms within the plugin's content handling processes, creating an environment where user-supplied data can be executed as script code within the context of the application.
The technical implementation of this stored cross-site scripting vulnerability occurs when administrators or users with posting privileges create or modify blog content through the hexo-admin interface. The plugin fails to properly sanitize or escape user input before storing and rendering the content, allowing malicious payloads to be persisted in the database and subsequently executed whenever the affected posts are viewed by other users. This stored nature of the vulnerability means that the malicious script remains active even after the initial injection, making it particularly dangerous for ongoing attacks. The flaw operates at the application layer and specifically targets the content rendering pipeline where post data transitions from user input to displayed output.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform a wide range of malicious activities including session hijacking, credential theft, data exfiltration, and privilege escalation within the affected system. An attacker could craft malicious posts containing scripts that steal cookies, redirect users to phishing sites, or even inject additional malicious content into the application. The vulnerability affects any user who has access to the hexo-admin interface, potentially compromising not only the integrity of the content but also the security of the entire blogging platform. This represents a significant threat to organizations relying on hexo-based content management systems for their web presence.
Security mitigations for this vulnerability should focus on immediate remediation through plugin updates to versions that address the XSS flaw, combined with comprehensive input validation and output encoding mechanisms. Organizations should implement proper content sanitization libraries that strip or encode potentially dangerous HTML and JavaScript content before storage. The fix should align with established security practices such as those outlined in the OWASP Top Ten and CWE-79 which specifically addresses cross-site scripting vulnerabilities. Additionally, implementing proper access controls and privilege separation within the hexo-admin interface can limit the potential impact of such vulnerabilities, ensuring that only authorized personnel can modify content. Regular security assessments and dependency updates remain crucial for maintaining the security posture of Node.js applications utilizing third-party plugins.
This vulnerability demonstrates the critical importance of proper input sanitization in web applications and aligns with ATT&CK technique T1566 which covers social engineering through malicious content. The stored nature of the XSS attack means that the threat persists until remediation occurs, making it particularly dangerous for environments where content management systems are frequently updated by multiple users. Organizations should also consider implementing Content Security Policy headers to provide additional defense-in-depth against such attacks, though this should not be considered a replacement for proper input validation and sanitization. The vulnerability serves as a reminder of the risks associated with third-party plugin integration in Node.js environments and the necessity of thorough security reviews before deployment.