CVE-2016-10858 in cPanel
Summary
by MITRE
cPanel before 11.54.0.0 allows unauthenticated arbitrary code execution via DNS NS entry poisoning (SEC-64).
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Analysis
by VulDB Data Team • 11/20/2023
The vulnerability identified as CVE-2016-10858 represents a critical security flaw in cPanel versions prior to 11.54.0.0 that enables unauthenticated arbitrary code execution through DNS NS entry poisoning techniques. This vulnerability falls under the category of command injection and privilege escalation, with significant implications for web hosting environments that rely on cPanel for server management. The flaw exploits the way cPanel handles DNS record updates, specifically targeting the NS (Name Server) record modification functionality that allows attackers to manipulate DNS configurations without proper authentication.
The technical implementation of this vulnerability occurs when cPanel fails to properly validate DNS NS record modifications, allowing malicious actors to inject arbitrary commands through specially crafted DNS entries. This weakness enables attackers to execute arbitrary code on the target system with the privileges of the cPanel user account, which often runs with elevated permissions. The vulnerability is particularly dangerous because it requires no authentication credentials to exploit, making it accessible to anyone who can influence DNS resolution for affected domains. The attack vector leverages DNS poisoning techniques where an attacker can manipulate DNS records to redirect traffic or execute malicious commands through the cPanel DNS management interface.
The operational impact of CVE-2016-10858 extends beyond simple code execution, as it can lead to complete system compromise and unauthorized access to sensitive data. Organizations using affected cPanel versions face risks including data breaches, system infiltration, and potential lateral movement within their network infrastructure. The vulnerability can be exploited to establish persistent backdoors, exfiltrate sensitive information, or use the compromised system as a launch point for further attacks. This makes the vulnerability particularly dangerous in shared hosting environments where multiple customers' data resides on the same infrastructure, potentially affecting numerous users simultaneously.
Security professionals should implement immediate mitigations including updating to cPanel version 11.54.0.0 or later, which contains the necessary patches to address the DNS NS entry poisoning vulnerability. Additional protective measures include implementing DNS security measures such as DNSSEC to prevent unauthorized DNS record modifications, monitoring DNS queries for suspicious patterns, and restricting direct DNS management access to trusted administrators only. Organizations should also consider implementing network segmentation and access controls to limit the potential impact of successful exploitation. The vulnerability aligns with CWE-77 and CWE-78 categories related to command injection, and corresponds to ATT&CK techniques involving privilege escalation and execution through legitimate system processes, emphasizing the need for comprehensive security controls beyond simple patch management.
This vulnerability demonstrates the critical importance of DNS security in web hosting environments and highlights how seemingly minor configuration flaws can lead to severe security consequences. The unauthenticated nature of the exploit makes it particularly concerning for organizations that do not maintain strict network monitoring and access controls, as attackers can exploit the vulnerability without detection. Regular security assessments and vulnerability scanning should include checks for outdated cPanel installations, as this vulnerability represents a common attack vector that has been widely documented in security threat intelligence feeds and exploit databases.