Description Preview
A critical vulnerability in the Cisco Discovery Protocol (CDP) implementation for Cisco NX-OS Software allows an unauthenticated, adjacent attacker to execute arbitrary code with administrative privileges or cause a device reload. The vulnerability stems from improper input validation in the CDP parser for certain message fields, which can lead to a stack overflow condition. An attacker in the same broadcast domain as the affected device can exploit this by sending a malicious CDP packet.
Overview
CVE-2020-3119 is a stack overflow vulnerability in Cisco NX-OS Software's CDP implementation. The flaw exists because the CDP parser fails to properly validate input for certain fields in CDP messages. This is classified as a CWE-787 (Out-of-bounds Write) vulnerability. Since CDP is a Layer 2 protocol, an attacker must be in the same broadcast domain (Layer 2 adjacent) as the vulnerable device to exploit it. Successful exploitation allows arbitrary code execution with administrative privileges or causes a device reload, potentially leading to complete device takeover.
Remediation
To address this vulnerability, administrators should:
- Update affected Cisco NX-OS Software to a patched version as specified in the Cisco Security Advisory (cisco-sa-20200205-nxos-cdp-rce).
- If immediate patching is not possible, consider these mitigations:
- Disable CDP on interfaces where it's not operationally required
- Implement proper network segmentation to limit the potential attack surface
- Monitor for suspicious CDP traffic in the network
- Review network security architecture to ensure proper segmentation of management networks.
- Follow Cisco's best practices for securing network infrastructure devices.
References
- Cisco Security Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-nxos-cdp-rce
- Packet Storm Security Advisory: http://packetstormsecurity.com/files/156203/Cisco-Discovery-Protocol-CDP-Remote-Device-Takeover.html
- MITRE CWE-787: https://cwe.mitre.org/data/definitions/787.html
- CVE-2020-3119 in the National Vulnerability Database
Industry ExposureMost to leastThis section illustrates the prevalence of a specific Common Vulnerabilities and Exposures (CVE) across various industries based on customer reports. The ranking displays industries from the most to least affected by this particular vulnerability, offering valuable insight into where this CVE has been most frequently observed. This information can help organizations within these sectors prioritize their security efforts, understand their relative risk exposure compared to their peers, and focus remediation strategies where they are most needed. By understanding the industry-specific impact, organizations can make more informed decisions regarding patching, resource allocation, and overall risk management related to this CVE.
This section illustrates the prevalence of a specific Common Vulnerabilities and Exposures (CVE) across various industries based on customer reports. The ranking displays industries from the most to least affected by this particular vulnerability, offering valuable insight into where this CVE has been most frequently observed. This information can help organizations within these sectors prioritize their security efforts, understand their relative risk exposure compared to their peers, and focus remediation strategies where they are most needed. By understanding the industry-specific impact, organizations can make more informed decisions regarding patching, resource allocation, and overall risk management related to this CVE.
- ManufacturingManufacturing: Low
- Public AdministrationPublic Administration: Low
- Health Care & Social AssistanceHealth Care & Social Assistance: Low
- Retail TradeRetail Trade: Low
- Finance and InsuranceFinance and Insurance: Low
- Transportation & WarehousingTransportation & Warehousing: Low
- Educational ServicesEducational Services: Low
- UtilitiesUtilities: Low
- Arts, Entertainment & RecreationArts, Entertainment & Recreation: Low
- Accommodation & Food ServicesAccommodation & Food Services: Low
- InformationInformation: Low
- Management of Companies & EnterprisesManagement of Companies & Enterprises: Low
- Other Services (except Public Administration)Other Services (except Public Administration): Low
- Administrative, Support, Waste Management & Remediation ServicesAdministrative, Support, Waste Management & Remediation Services: Low
- Agriculture, Forestry Fishing & HuntingAgriculture, Forestry Fishing & Hunting: Low
- ConstructionConstruction: Low
- MiningMining: Low
- Professional, Scientific, & Technical ServicesProfessional, Scientific, & Technical Services: Low
- Real Estate Rental & LeasingReal Estate Rental & Leasing: Low
- Wholesale TradeWholesale Trade: Low
