CVE-2016-10841 in cPanel
Summary
by MITRE
The bin/mkvhostspasswd script in cPanel before 11.54.0.4 discloses password hashes (SEC-73).
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Analysis
by VulDB Data Team • 11/20/2023
The vulnerability identified as CVE-2016-10841 affects cPanel versions prior to 11.54.0.4 and specifically targets the bin/mkvhostspasswd script which is designed to manage password hashes for hosting accounts. This issue represents a critical information disclosure flaw that allows unauthorized users to access sensitive authentication data. The vulnerability stems from improper access controls within the script that fails to properly validate user permissions before exposing password hash information. According to security advisory SEC-73, this weakness enables attackers to retrieve password hashes without proper authentication, potentially compromising the security of multiple hosting accounts managed through the affected cPanel instance. The flaw directly violates fundamental security principles of least privilege and access control enforcement, creating an avenue for credential compromise at scale.
The technical implementation of this vulnerability occurs within the mkvhostspasswd script where authentication checks are either missing or inadequately enforced. When the script processes requests for password hash retrieval, it fails to verify whether the requesting user possesses appropriate administrative privileges or ownership rights to access the target account information. This design flaw allows any user with access to execute the script to obtain password hashes from other hosting accounts, effectively bypassing the intended security boundaries. The vulnerability is classified under CWE-284 which specifically addresses improper access control mechanisms, and aligns with ATT&CK technique T1078 which covers valid accounts as a means of gaining access to systems. The script's execution context appears to lack proper input validation and privilege escalation checks, making it susceptible to exploitation by malicious actors who may have gained limited access to the system through other vectors.
The operational impact of CVE-2016-10841 extends beyond simple information disclosure, as password hashes obtained through this vulnerability can be subjected to offline brute force attacks or distributed computing attacks using tools like john the ripper or hashcat. This compromise enables attackers to potentially gain unauthorized access to multiple hosting accounts simultaneously, especially when users employ weak or reused passwords across different systems. The vulnerability affects the entire cPanel ecosystem and can result in complete account takeover scenarios, allowing attackers to modify website content, steal customer data, and potentially use compromised accounts as launching points for further attacks within the hosting environment. Organizations running affected cPanel versions face significant risk of data breaches, service disruption, and potential regulatory compliance violations. The exposure of password hashes also enables attackers to conduct credential stuffing attacks against other services where users may have reused passwords, amplifying the overall security impact.
Mitigation strategies for CVE-2016-10841 center on immediate software updates to cPanel version 11.54.0.4 or later where the vulnerability has been patched. System administrators should ensure all affected cPanel installations are updated promptly to prevent exploitation. Additional protective measures include implementing network segmentation to limit access to the bin/mkvhostspasswd script, enforcing strict file permissions on the script and related configuration files, and monitoring system logs for unauthorized script execution attempts. Security teams should conduct comprehensive audits of all cPanel installations to identify and remediate similar access control weaknesses in other scripts or components. The fix implemented in cPanel 11.54.0.4 addresses the core issue by strengthening access control validation within the mkvhostspasswd script, ensuring that only authorized users with appropriate privileges can retrieve password hash information. Organizations should also implement multi-factor authentication for administrative accounts and consider implementing intrusion detection systems to monitor for suspicious activity related to password hash retrieval operations. This vulnerability serves as a reminder of the critical importance of maintaining up-to-date software and proper access control implementations in web hosting environments where sensitive user data is processed and stored.