CVE-2018-20908 in cPanel
Summary
by MITRE
cPanel before 71.9980.37 allows arbitrary file-read operations during pkgacct custom template handling (SEC-435).
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Analysis
by VulDB Data Team • 07/18/2020
The vulnerability identified as CVE-2018-20908 affects cPanel versions prior to 71.9980.37 and represents a critical arbitrary file read flaw within the pkgacct custom template handling functionality. This vulnerability falls under the category of insecure direct object reference issues and can be classified as CWE-22 according to the Common Weakness Enumeration framework. The flaw exists in the way cPanel processes custom template files during the pkgacct backup operation, which is a core administrative function used to create backups of accounts and their configurations.
The technical implementation of this vulnerability stems from insufficient input validation and sanitization within the pkgacct module. When administrators or users interact with custom template handling features, the system fails to properly validate file paths and names, allowing attackers to manipulate the template processing logic to read arbitrary files from the filesystem. This occurs because the application does not adequately restrict file access controls during template rendering, particularly when dealing with user-supplied template names or paths that could contain directory traversal sequences or other malicious input patterns.
The operational impact of this vulnerability is severe as it enables attackers to extract sensitive information from the compromised system without proper authentication or authorization. An attacker could potentially read critical system files including configuration files, database credentials, user account details, and other sensitive data stored within the cPanel environment. This arbitrary file reading capability directly maps to ATT&CK technique T1005 which involves data from local system sources, and could be leveraged to escalate privileges and move laterally within the compromised infrastructure. The vulnerability affects the integrity and confidentiality of the entire cPanel installation, potentially exposing multiple accounts and their associated data to unauthorized access.
Mitigation strategies for CVE-2018-20908 require immediate implementation of the vendor-provided security patch available in cPanel version 71.9980.37 and subsequent releases. Organizations should also implement additional defensive measures including restricting access to pkgacct functionality to trusted administrative users only, implementing proper file access controls and monitoring for unusual file access patterns, and conducting regular security assessments of custom templates. Network segmentation and privileged access controls should be enforced to limit the potential impact of successful exploitation attempts. The vulnerability highlights the importance of input validation and proper access control mechanisms in web applications, particularly those handling administrative functions and user-supplied data within critical system components.