CVE-2019-1587 in NX-OS
Summary
by MITRE
A vulnerability in Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an authenticated, remote attacker to access sensitive information. The vulnerability occurs because the affected software does not properly validate user-supplied input. An attacker could exploit this vulnerability by issuing certain commands with filtered query results on the device. This action may cause returned messages to display confidential system information. A successful exploit could allow the attacker to read sensitive information on the device.
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Analysis
by VulDB Data Team • 09/12/2023
The vulnerability identified as CVE-2019-1587 affects Cisco Nexus 9000 Series Fabric Switches operating in Application Centric Infrastructure (ACI) mode, representing a critical security weakness that undermines the integrity of sensitive data protection mechanisms. This flaw resides within the software implementation that governs how the switch processes and validates user input, creating an avenue for unauthorized information disclosure. The vulnerability specifically manifests when the system fails to properly validate user-supplied input during command execution, allowing malicious actors to craft specific queries that bypass normal access controls and reveal confidential system information.
The technical exploitation of this vulnerability leverages the insufficient input validation mechanisms within the ACI software stack, enabling an authenticated remote attacker to manipulate query parameters and retrieve filtered results that contain sensitive system data. The flaw operates through the manipulation of command structures that should normally restrict access to confidential information, but due to inadequate validation checks, certain command sequences can return detailed system information that should remain protected. This type of vulnerability falls under the CWE-20 category of "Improper Input Validation," which represents one of the most common and dangerous classes of security flaws in network infrastructure devices.
From an operational perspective, this vulnerability presents significant risk to organizations relying on Cisco Nexus 9000 switches in ACI mode, as it allows remote attackers with valid credentials to access confidential system information without requiring additional privileges or physical access to the network equipment. The impact extends beyond simple information disclosure, potentially enabling attackers to gather intelligence about network topology, device configurations, and system internals that could facilitate more sophisticated attacks. The vulnerability's remote exploitability means that attackers can target these switches from outside the local network perimeter, making it particularly dangerous in environments where network segmentation is not properly implemented.
Organizations should implement immediate mitigations including applying the latest security patches provided by Cisco, which address the input validation issues in the affected software components. Network segmentation strategies should be reinforced to limit the potential impact of successful exploitation attempts, while monitoring systems should be enhanced to detect anomalous command patterns that might indicate exploitation attempts. The vulnerability's classification aligns with ATT&CK technique T1083 (File and Directory Discovery) and T1005 (Data from Local System), indicating that exploitation could lead to broader reconnaissance and data collection activities. Additionally, implementing strict access controls and limiting administrative privileges to only necessary personnel helps reduce the attack surface and potential damage from successful exploitation attempts.