CVE-2017-18457 in cPanel
Summary
by MITRE
cPanel before 62.0.17 allows arbitrary file-read operations via WHM /styled/ URLs (SEC-218).
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Analysis
by VulDB Data Team • 07/19/2020
The vulnerability identified as CVE-2017-18457 represents a critical arbitrary file read flaw within cPanel software versions prior to 62.0.17. This security weakness specifically affects the WHM (Web Host Manager) interface and exploits improper input validation mechanisms within the /styled/ URL handling functionality. The vulnerability stems from insufficient sanitization of user-supplied input parameters that are processed by the web server when handling requests to styled resources, creating an opportunity for malicious actors to access files outside the intended directory structure.
The technical exploitation of this vulnerability occurs through crafted HTTP requests that manipulate the URL parameters used by the styled interface components. Attackers can construct malicious URLs that bypass normal file access controls and retrieve sensitive files from the server filesystem. This includes potentially accessing configuration files, database credentials, user data, and other privileged information that should remain protected from unauthorized access. The flaw operates at the application layer and leverages path traversal techniques that are commonly classified under CWE-22 - Improper Limitation of a Pathname to a Restricted Directory.
From an operational impact perspective, this vulnerability presents a severe risk to hosting environments that rely on cPanel for web server management. Successful exploitation can lead to complete compromise of the hosting infrastructure, allowing attackers to exfiltrate sensitive data, escalate privileges, and potentially establish persistent access. The vulnerability affects not just individual user accounts but can potentially provide access to system-wide configuration data and administrative credentials. Security professionals should note that this flaw aligns with ATT&CK technique T1213.002 - Data from Information Repositories, as it enables unauthorized access to stored data through improper access control mechanisms.
The remediation strategy for CVE-2017-18457 requires immediate deployment of cPanel version 62.0.17 or later, which includes patches addressing the path traversal vulnerability in the WHM styled interface. Organizations should also implement network-level controls such as web application firewalls to monitor and block suspicious URL patterns targeting the affected interface. Additionally, system administrators should conduct thorough audits of file permissions and access controls to ensure that no additional attack vectors exist within the hosting environment. Regular security assessments of web applications and server configurations remain essential to prevent similar vulnerabilities from emerging in other components of the hosting infrastructure.