CVE-2016-6414 in IOS
Summary
by MITRE
iox in Cisco IOS, possibly 15.6 and earlier, and IOS XE, possibly 3.18 and earlier, allows local users to execute arbitrary IOx Linux commands on the guest OS via crafted iox command-line options, aka Bug ID CSCuz59223.
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Analysis
by VulDB Data Team • 09/24/2024
The vulnerability identified as CVE-2016-6414 represents a critical local privilege escalation flaw within Cisco's IOx platform, which operates as a Linux-based application framework embedded within Cisco IOS and IOS XE operating systems. This vulnerability specifically affects versions 15.6 and earlier of IOS, as well as IOS XE versions 3.18 and earlier, creating a persistent security risk across multiple Cisco networking devices. The IOx framework enables the execution of Linux applications directly on Cisco routers and switches, providing extended functionality but also introducing additional attack surface areas that can be exploited by malicious actors with local access to the device.
The technical exploitation of this vulnerability occurs through crafted command-line options within the IOx subsystem, allowing local users to inject and execute arbitrary Linux commands within the guest operating system environment. This represents a classic command injection vulnerability that bypasses normal access controls and privilege boundaries within the IOx framework. The flaw stems from inadequate input validation and sanitization of command-line parameters passed to the IOx subsystem, enabling attackers to manipulate the execution flow and gain unauthorized access to the underlying Linux environment. According to CWE classification, this vulnerability maps to CWE-77, which specifically addresses command injection flaws where untrusted data is incorporated into system commands without proper validation or sanitization.
The operational impact of CVE-2016-6414 is severe and multifaceted, as local users who can access the device's command-line interface can leverage this vulnerability to execute arbitrary code with elevated privileges within the IOx guest environment. This capability allows attackers to potentially escalate their privileges beyond the initial local access level, gain access to sensitive system information, modify or delete critical files, and establish persistent backdoors within the network infrastructure. The vulnerability affects the fundamental security model of Cisco's IOx implementation, undermining the isolation between the host IOS operating system and the guest Linux environment. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and command execution within compromised systems, representing a significant threat to network infrastructure security.
Mitigation strategies for CVE-2016-6414 primarily focus on immediate software updates and patches provided by Cisco to address the underlying command injection flaw in the IOx subsystem. Organizations should prioritize applying the relevant security patches released by Cisco, which typically include enhanced input validation mechanisms and proper sanitization of command-line parameters within the IOx framework. Additionally, network administrators should implement strict access controls and monitor command-line usage on affected devices to detect potential exploitation attempts. The vulnerability highlights the importance of least privilege principles, as limiting local access to network devices can significantly reduce the attack surface. Security teams should also consider disabling IOx functionality entirely on devices where it is not required, as this eliminates the vulnerability entirely while maintaining network functionality. Regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of the vulnerable IOx versions within the network infrastructure.