CVE-2016-6470 in Hybrid Media Service
Summary
by MITRE
A vulnerability in the installation procedure of the Cisco Hybrid Media Service could allow an authenticated, local attacker to elevate privileges to the root level. More Information: CSCvb81344. Known Affected Releases: 1.0.
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Analysis
by VulDB Data Team • 07/05/2019
The vulnerability identified as CVE-2016-6470 represents a critical privilege escalation flaw within Cisco's Hybrid Media Service installation process. This weakness specifically targets the local installation procedures of the service, creating an exploitable condition that allows authenticated users with limited privileges to escalate their access rights to the root level of the system. The vulnerability stems from improper privilege handling during the installation phase, where the service fails to adequately validate or restrict the execution context of installation components. This flaw is particularly concerning because it leverages the legitimate installation process to bypass normal security boundaries, making it difficult to detect through conventional monitoring mechanisms. The issue was documented under CSCvb81344 and affected only version 1.0 of the Hybrid Media Service, indicating a specific implementation flaw that likely existed in the initial release without proper privilege separation mechanisms. The vulnerability's impact extends beyond simple access control as it fundamentally undermines the system's security model by allowing local attackers to gain administrative control through legitimate installation pathways.
The technical exploitation of CVE-2016-6470 occurs through a flaw in the installation procedure's privilege management where the service does not properly enforce user context restrictions during component installation. This vulnerability can be categorized under CWE-276, which addresses improper privilege management, and more specifically aligns with CWE-782, focusing on exposed service in privileged installation. Attackers can leverage this weakness by executing installation commands with elevated privileges while maintaining their authenticated session, effectively allowing them to bypass normal authentication checks. The flaw likely manifests through improper handling of file permissions, directory ownership, or process execution contexts during the installation sequence. From an operational perspective, this vulnerability creates a persistent backdoor for attackers who can maintain elevated access even after initial compromise, as the privilege escalation occurs during the installation process itself rather than through runtime exploitation. The attack vector requires local authentication, meaning an attacker must first establish a valid user session before attempting the privilege escalation, but once achieved, the elevated privileges provide complete system control. This weakness directly violates the principle of least privilege and demonstrates inadequate sandboxing or privilege separation during the service installation lifecycle.
The operational impact of CVE-2016-6470 extends beyond immediate system compromise to include long-term security implications for organizations utilizing Cisco Hybrid Media Service. Once exploited, attackers can establish persistent access, modify system configurations, install additional malicious software, or exfiltrate sensitive data without detection. The vulnerability's nature as a privilege escalation flaw means that it can be used to bypass security controls such as firewalls, intrusion detection systems, and other network-based protections since the attacker operates at the system level with full administrative capabilities. Organizations may experience unauthorized access to critical infrastructure components, potential data breaches, and compromised system integrity. The impact is particularly severe in environments where the Hybrid Media Service is deployed on critical network equipment or servers where elevated privileges could provide access to sensitive corporate networks or customer data. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and can be used to establish persistence, move laterally within networks, and access sensitive information. The vulnerability also affects compliance requirements for systems handling sensitive data, as it represents a fundamental failure in maintaining proper access controls and system integrity. Security teams must consider the potential for this vulnerability to be used in conjunction with other attack vectors, creating a more comprehensive compromise scenario that could affect multiple systems within an organization's infrastructure.
Mitigation strategies for CVE-2016-6470 should focus on immediate patching and operational controls to prevent exploitation. Cisco has released updates addressing this vulnerability, and organizations should prioritize applying the relevant security patches to all affected systems running version 1.0 of the Hybrid Media Service. In the absence of immediate patching, organizations can implement additional controls such as restricting local authentication privileges, monitoring installation processes for suspicious activity, and implementing strict access controls for system directories and files. Network segmentation can help limit the potential impact if exploitation occurs, while enhanced logging and monitoring of installation activities can provide early detection of attempted exploitation. System hardening measures including disabling unnecessary services, implementing proper file permissions, and ensuring that installation processes run with minimal required privileges can reduce the attack surface. Organizations should also conduct thorough vulnerability assessments to identify other potential privilege escalation vulnerabilities in their infrastructure and implement principle of least privilege policies. Regular security audits and penetration testing can help identify similar weaknesses in other systems and services that may be vulnerable to similar exploitation techniques. The vulnerability serves as a reminder of the critical importance of proper privilege management during software installation processes and highlights the need for comprehensive security testing of installation procedures to prevent such flaws from being introduced into production environments.