CVE-2017-18482 in cPanel
Summary
by MITRE
cPanel before 62.0.4 allows resellers to use the WHM enqueue_transfer_item API for queueing non-rearrange modules (SEC-213).
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Analysis
by VulDB Data Team • 07/21/2020
The vulnerability identified as CVE-2017-18482 affects cPanel versions prior to 62.0.4 and represents a significant authorization flaw within the WHM API interface. This issue specifically impacts reseller accounts and exploits a weakness in the enqueue_transfer_item API function that should have restricted certain operations to administrative users only. The vulnerability stems from inadequate access controls that permit resellers to queue non-rearrange modules through the API, effectively bypassing intended security boundaries that separate reseller privileges from administrative functions. This misconfiguration creates a pathway for unauthorized actions that should remain restricted to system administrators.
The technical flaw manifests in the improper validation of user permissions within the WHM API implementation. When resellers invoke the enqueue_transfer_item function, the system fails to properly verify whether the requesting account possesses the necessary administrative privileges to perform the specific operation. This authorization bypass occurs because the API does not adequately distinguish between different types of modules that can be queued through the transfer mechanism. The vulnerability specifically allows resellers to queue modules that are not designed for rearrangement, which typically requires elevated privileges and system-level access that reseller accounts should not possess. This flaw aligns with CWE-284, which addresses improper access control mechanisms in software applications.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it creates potential for unauthorized system modifications and data manipulation. Resellers could potentially queue malicious or unauthorized modules for transfer, leading to system instability, data corruption, or unauthorized access to sensitive system components. The vulnerability also presents risks for privilege abuse within shared hosting environments where reseller accounts may have access to multiple customer accounts and their associated data. Attackers could exploit this weakness to escalate their privileges, gain access to restricted system functions, or potentially compromise the entire hosting infrastructure. This scenario particularly concerns organizations using cPanel for managing multiple customer accounts where reseller permissions are critical for maintaining security boundaries.
Mitigation strategies for CVE-2017-18482 require immediate implementation of the available security patches provided by cPanel, specifically upgrading to version 62.0.4 or later. Organizations should also conduct comprehensive audits of reseller account permissions to ensure that only trusted administrators have access to sensitive API functions. Network segmentation and API access controls should be implemented to restrict direct API calls from reseller accounts to critical system functions. Additionally, monitoring and logging of API activity should be enhanced to detect unauthorized access attempts and privilege escalation attempts. The vulnerability demonstrates the importance of proper API security implementation and access control validation as outlined in the ATT&CK framework under privilege escalation techniques. System administrators should also consider implementing role-based access controls that enforce the principle of least privilege, ensuring that reseller accounts cannot access functions that require administrative permissions. Regular security assessments and penetration testing should be conducted to identify similar authorization bypass vulnerabilities in other system components and API interfaces.