CVE-2017-18436 in cPanel
Summary
by MITRE
cPanel before 64.0.21 allows demo accounts to read files via a Fileman::getfileactions API2 call (SEC-239).
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Analysis
by VulDB Data Team • 07/19/2020
The vulnerability identified as CVE-2017-18436 represents a critical access control flaw within the cPanel web hosting control panel software. This issue affects versions prior to 64.0.21 and specifically targets the Fileman::getfileactions API2 call which is designed to retrieve file actions and permissions within the file manager interface. The flaw enables unauthorized access to sensitive files through demo accounts that should typically be restricted from accessing certain system resources. This vulnerability directly violates fundamental security principles of least privilege and proper access control enforcement within web applications.
The technical implementation of this vulnerability stems from inadequate input validation and permission checking within the Fileman::getfileactions API endpoint. When demo accounts make requests to this specific API call, the system fails to properly verify whether the requesting user has sufficient privileges to access the requested files. The vulnerability exists because the API does not adequately authenticate or authorize the file access requests based on the account type and permissions assigned to demo users. This creates a path where unauthorized users can bypass normal file access restrictions and potentially read sensitive system files, configuration data, or user information that should remain protected.
The operational impact of this vulnerability extends beyond simple unauthorized file access as it provides attackers with potential entry points for more sophisticated attacks. Demo accounts typically have limited functionality and are intended for demonstration purposes only, but this flaw allows them to escalate their privileges and access restricted resources. Attackers could exploit this vulnerability to obtain sensitive information such as database credentials, configuration files, user data, or system files that could be used for further exploitation. The vulnerability also represents a significant risk to hosting providers as it could enable attackers to compromise multiple customer accounts or gain access to system-level information that could facilitate broader attacks against the hosting infrastructure.
Organizations should implement immediate mitigations including updating to cPanel version 64.0.21 or later which contains the necessary patches to address this access control flaw. Additionally, administrators should review and tighten the permissions assigned to demo accounts to ensure they cannot access file system resources beyond their intended demonstration scope. The vulnerability aligns with CWE-285 which addresses improper authorization in software systems and can be categorized under ATT&CK technique T1078 for Valid Accounts and T1083 for File and Directory Discovery. Security monitoring should be enhanced to detect unusual API calls to file management endpoints, particularly from accounts with limited privileges that might indicate exploitation attempts. Regular security audits of API endpoints and access control mechanisms should be conducted to identify similar vulnerabilities in other system components and maintain overall security posture.