CVE-2017-8383 in Craft
Summary
by MITRE
Craft CMS before 2.6.2976 does not properly restrict viewing the contents of files in the craft/app/ folder.
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Analysis
by VulDB Data Team • 09/22/2020
The vulnerability identified as CVE-2017-8383 affects Craft CMS versions prior to 2.6.2976 and represents a critical access control flaw that allows unauthorized users to view sensitive files within the craft/app/ directory structure. This issue stems from inadequate file access restrictions that fail to properly validate user permissions before serving content from protected application folders. The vulnerability exists in the core file serving mechanism of the CMS, where the application does not adequately verify whether a requesting user possesses the necessary authorization to access specific files within the application directory tree. This flaw creates a path for attackers to potentially extract sensitive application code, configuration files, and other proprietary assets that should remain protected from public access.
The technical implementation of this vulnerability involves the application's failure to enforce proper authentication and authorization checks when processing requests for files within the craft/app/ folder. Attackers can exploit this weakness by directly accessing specific file paths that would normally be restricted, potentially gaining insights into the application's internal architecture, database connection details, and other sensitive information that could be leveraged for further exploitation. The flaw operates at the application layer and specifically affects the file serving component that handles requests for various application resources, making it particularly dangerous as it can expose the underlying system configuration and application logic to unauthorized parties. This vulnerability aligns with CWE-284, which describes improper access control issues in software systems, and represents a clear violation of the principle of least privilege in system security design.
The operational impact of this vulnerability extends beyond simple information disclosure, as the exposed files could contain database credentials, encryption keys, or other sensitive configuration data that could enable attackers to escalate their privileges within the system. An attacker who successfully exploits this vulnerability could gain access to the application's internal codebase, potentially identifying additional security weaknesses or attack vectors that could lead to complete system compromise. The exposure of application files also provides valuable intelligence for attackers conducting reconnaissance activities, allowing them to understand the application's structure and identify potential targets for further exploitation. This vulnerability creates opportunities for attackers to perform advanced persistent threat activities and could facilitate more sophisticated attacks such as privilege escalation or lateral movement within the network infrastructure.
Organizations affected by this vulnerability should immediately upgrade to Craft CMS version 2.6.2976 or later, which includes proper access control mechanisms that prevent unauthorized file access. Security teams should also conduct comprehensive audits of their application directories to identify any files that may have been previously exposed, and implement additional monitoring to detect unauthorized access attempts to sensitive file paths. The remediation process should include reviewing all file access controls and ensuring that proper authentication mechanisms are in place before any file serving operations occur. Organizations should also consider implementing web application firewalls and intrusion detection systems to help identify and block attempts to access restricted application files. This vulnerability demonstrates the critical importance of proper access control implementation and highlights the need for regular security assessments to identify and remediate similar issues in application code. The flaw serves as a reminder of the necessity for secure coding practices and proper input validation in web applications, as outlined in various security frameworks including those referenced in the ATT&CK framework for application layer threats.