CVE-2013-1208 in NX-OS
Summary
by MITRE
The encryption functionality in Cisco NX-OS on the Nexus 1000V does not properly handle Virtual Supervisor Module (VSM) to Virtual Ethernet Module (VEM) communication, which allows remote attackers to intercept or modify network traffic by leveraging certain Layer 2 or Layer 3 access, aka Bug ID CSCud14691.
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Analysis
by VulDB Data Team • 05/04/2019
The vulnerability described in CVE-2013-1208 represents a critical flaw in Cisco NX-OS software running on Nexus 1000V virtual switches, specifically impacting the encryption mechanisms used for secure communication between Virtual Supervisor Module and Virtual Ethernet Module components. This weakness stems from improper handling of cryptographic protocols during inter-module communication, creating a significant security gap that adversaries can exploit to compromise network integrity and confidentiality.
The technical implementation flaw occurs within the encryption stack of the Nexus 1000V platform where the VSM and VEM components fail to properly establish secure cryptographic channels for their communication. This improper handling allows attackers with Layer 2 or Layer 3 network access to potentially intercept or modify traffic flowing between these modules. The vulnerability specifically affects the encryption functionality that should ensure secure communication between the virtual supervisor and virtual ethernet modules, creating a man-in-the-middle attack vector that can be leveraged by remote threat actors.
From an operational impact perspective, this vulnerability undermines the fundamental security assurances provided by the Nexus 1000V virtual switch platform, potentially allowing attackers to access sensitive network data, modify traffic flows, or disrupt network operations. The attack surface is particularly concerning as it requires only basic Layer 2 or Layer 3 access, making it accessible to threat actors who may already have some network presence or privileges. The vulnerability affects the overall security posture of data center networks that rely on Cisco Nexus 1000V virtual switches for their virtualization infrastructure.
Security professionals should consider this vulnerability in the context of the CWE-310 weakness category, which encompasses cryptographic issues and improper implementation of encryption mechanisms. The attack vectors align with ATT&CK techniques related to credential access and network sniffing, as the vulnerability enables unauthorized traffic interception and modification. Organizations should implement immediate mitigations including network segmentation, enhanced monitoring of VSM-VEM communication, and deployment of additional security controls to prevent exploitation of this cryptographic weakness.
The remediation approach should involve applying Cisco's official security patches and updates to address the encryption implementation flaw in the NX-OS software. Network administrators should also consider implementing additional monitoring solutions to detect anomalous VSM-VEM communication patterns and establish network access controls to limit Layer 2 and Layer 3 access to only authorized entities. Regular security assessments of virtualized network infrastructure should be conducted to identify similar cryptographic implementation weaknesses that could compromise network security.