CVE-2019-1607 in NX-OS
Summary
by MITRE
A vulnerability in the CLI of Cisco NX-OS Software could allow an authenticated, local attacker to execute arbitrary commands on the underlying operating system of an affected device. The vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input as the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands on the underlying operating system with elevated privileges. An attacker would need valid administrator credentials to exploit this vulnerability. Nexus 7000 and 7700 Series Switches are affected in versions prior to 6.2(22), 7.3(3)D1(1), and 8.2(3).
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Analysis
by VulDB Data Team • 07/31/2023
This vulnerability resides within the command line interface of Cisco NX-OS software, representing a critical privilege escalation flaw that enables authenticated local attackers to execute arbitrary operating system commands. The vulnerability stems from inadequate input validation mechanisms within specific CLI commands, creating a pathway for malicious input injection that bypasses normal security controls. The flaw specifically affects Cisco Nexus 7000 and 7700 Series Switches, with affected versions including those prior to 6.2(22), 7.3(3)D1(1), and 8.2(3), indicating a widespread impact across multiple software releases. This type of vulnerability falls under CWE-20, which addresses improper input validation, and represents a classic example of command injection in network device management interfaces.
The technical exploitation of this vulnerability requires an attacker to possess valid administrator credentials, establishing a baseline authentication requirement that limits the attack surface but does not eliminate the risk. Once authenticated, the attacker can leverage the insufficient argument validation to inject malicious commands that execute with elevated privileges on the underlying operating system. This privilege escalation capability means that even if the attacker initially gains access through legitimate administrative channels, the vulnerability allows them to elevate their privileges beyond normal administrative boundaries and potentially gain root-level access to the device's operating system. The attack vector specifically targets CLI command arguments, making it particularly dangerous as it operates within the expected administrative interface rather than requiring specialized attack tools or techniques.
The operational impact of this vulnerability extends far beyond simple command execution, as it fundamentally compromises the security posture of affected network infrastructure. An attacker who successfully exploits this vulnerability can potentially gain complete control over the affected switch, enabling them to modify network configurations, redirect traffic, disable security features, or establish persistence mechanisms within the network. This capability directly violates the principle of least privilege and undermines the integrity of the network device's security model. The vulnerability's presence in multiple software versions suggests a prolonged window of exposure, potentially allowing attackers to maintain persistent access to network infrastructure without detection. From an attacker perspective, this vulnerability aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1548.001 for abuse of privileges, making it a valuable target for both insider threats and externally targeting compromised administrative accounts.
Organizations should prioritize immediate remediation through official Cisco software updates and patches addressing this vulnerability in affected versions. The patching process should include comprehensive testing in non-production environments to ensure compatibility with existing network configurations and operational procedures. Network segmentation and access control measures should be strengthened to limit administrative access to only essential personnel, while implementing additional monitoring for unusual CLI command patterns that might indicate exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify any other potential command injection vulnerabilities within the network infrastructure. Administrative accounts should be configured with the principle of least privilege, and multi-factor authentication should be implemented where possible to add additional layers of security. The vulnerability serves as a reminder of the critical importance of input validation in network device management interfaces and the potential consequences when such validation mechanisms fail, emphasizing the need for robust security practices in network infrastructure management.