CVE-2018-0314 in NX-OS
Summary
by MITRE
A vulnerability in the Cisco Fabric Services (CFS) component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to execute arbitrary code on an affected device. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packet headers when the software processes packet data. An attacker could exploit this vulnerability by sending a maliciously crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to cause a buffer overflow condition on the device, which could allow the attacker to execute arbitrary code on the device. This vulnerability affects the following if configured to use Cisco Fabric Services: Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvd69943, CSCve02429, CSCve02433, CSCve02435, CSCve02445, CSCve04859.
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Analysis
by VulDB Data Team • 03/28/2023
The vulnerability described in CVE-2018-0314 represents a critical buffer overflow flaw within Cisco's Fabric Services (CFS) implementation across multiple network infrastructure devices. This weakness resides in the insufficient validation of packet headers during the processing of Cisco Fabric Services data, creating a pathway for remote code execution without authentication. The vulnerability specifically targets the FXOS Software and NX-OS Software components, affecting a broad range of Cisco networking equipment including firewalls, switches, and fabric interconnects. The flaw manifests when the affected software fails to properly validate incoming CFS packet headers, allowing maliciously crafted packets to trigger memory corruption conditions that can be exploited for arbitrary code execution.
The technical exploitation of this vulnerability follows a well-defined attack pattern that aligns with common remote code execution vectors documented in the cybersecurity landscape. Attackers can craft specially formatted Cisco Fabric Services packets and transmit them to vulnerable devices, bypassing authentication requirements entirely. The buffer overflow condition occurs during packet processing when the software does not adequately check the size or structure of incoming headers, leading to memory corruption that can be leveraged to execute malicious code with the privileges of the affected process. This type of vulnerability falls under the CWE-121 buffer overflow category, specifically CWE-125 out-of-bounds read conditions that can lead to arbitrary code execution, making it particularly dangerous for network infrastructure devices where such attacks can compromise entire network segments.
The operational impact of this vulnerability extends across numerous Cisco product lines that utilize CFS functionality, including the Firepower 4100 Series Next-Generation Firewalls, various Nexus switch platforms, MDS 9000 series switches, and UCS fabric interconnects. The attack surface is particularly concerning given that these devices typically operate in critical network infrastructure roles, making successful exploitation capable of causing widespread disruption. The vulnerability affects devices in both standalone and integrated configurations, meaning that even properly isolated network segments could be compromised if attackers can reach the affected services. This represents a significant concern for enterprise network security as the attack requires no authentication credentials and can be executed remotely, potentially allowing attackers to establish persistent access to critical network infrastructure.
The exploitation of CVE-2018-0314 aligns with tactics described in the MITRE ATT&CK framework, particularly in the execution and privilege escalation phases where attackers leverage buffer overflow vulnerabilities to gain code execution privileges. The vulnerability's characteristics make it suitable for automated exploitation campaigns, as demonstrated by various threat actor groups that have targeted similar network infrastructure flaws. Organizations should implement immediate mitigations including disabling CFS functionality when not required, applying security patches released by Cisco, and implementing network segmentation controls to limit the attack surface. The vulnerability's classification as a remote code execution flaw necessitates comprehensive monitoring of network traffic for suspicious CFS packet patterns and implementation of intrusion detection systems capable of identifying such malicious traffic patterns. Cisco's bug IDs CSCvd69943 through CSCve04859 indicate multiple related issues that were addressed through coordinated security updates, emphasizing the need for thorough patch management and vulnerability assessment processes across affected infrastructure.