CVE-2016-10838 in cPanel
Summary
by MITRE
cPanel before 11.54.0.4 allows arbitrary file-read operations via the bin/fmq script (SEC-70).
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Analysis
by VulDB Data Team • 11/20/2023
The vulnerability identified as CVE-2016-10838 represents a critical security flaw in cPanel versions prior to 11.54.0.4 that enables unauthorized file read operations through the bin/fmq script. This issue falls under the category of insecure direct object reference vulnerabilities and specifically relates to improper input validation within the cPanel administrative interface. The flaw exists in the way the system handles file paths and object references, allowing malicious actors to bypass normal access controls and retrieve arbitrary files from the server filesystem.
The technical implementation of this vulnerability occurs within the bin/fmq script which processes file management operations without adequate sanitization of user-supplied input. When the script receives file path parameters, it fails to properly validate or sanitize these inputs, creating an opportunity for path traversal attacks. Attackers can manipulate the script's parameters to navigate through the filesystem and access files that should normally be restricted to authorized users only. This vulnerability directly maps to CWE-22 which describes improper limitation of a pathname to a restricted directory, commonly known as path traversal or directory traversal attacks.
The operational impact of this vulnerability is severe as it provides attackers with the ability to read sensitive files that may contain database credentials, configuration settings, application source code, or other confidential information. The consequences extend beyond simple data exposure, as successful exploitation could lead to full system compromise through the acquisition of authentication tokens, private keys, or other critical system components. The vulnerability affects the integrity and confidentiality of the cPanel environment, potentially exposing multiple domains and accounts managed through the same interface. This type of attack aligns with techniques described in the ATT&CK framework under T1005 - Data from Local System and T1078 - Valid Accounts, as attackers can leverage compromised cPanel instances to escalate privileges and maintain persistent access.
Organizations running vulnerable cPanel versions face significant risk of data breaches, regulatory violations, and operational disruption. The vulnerability can be exploited by attackers with minimal technical expertise, making it particularly dangerous in environments where multiple users have access to the cPanel interface. The attack surface is broad as cPanel manages numerous web hosting accounts and applications, potentially allowing attackers to access multiple victim systems from a single successful exploitation. Remediation requires immediate patching to cPanel version 11.54.0.4 or later, which includes proper input validation and sanitization measures for the affected bin/fmq script. Additionally, implementing network segmentation, access controls, and monitoring for unusual file access patterns can help detect and prevent exploitation attempts. Organizations should also conduct thorough security assessments of their hosting environments to identify other potential vulnerabilities and ensure comprehensive protection against similar threats that may exist within their infrastructure.