Description Preview
A vulnerability in the file system on the pluggable USB 3.0 Solid State Drive (SSD) for Cisco IOS XE Software could allow an authenticated, physical attacker to remove the USB 3.0 SSD and modify sensitive areas of the file system, including the namespace container protections. The vulnerability occurs because the USB 3.0 SSD control data is not stored on the internal boot flash. An attacker could exploit this vulnerability by removing the USB 3.0 SSD, modifying or deleting files on the USB 3.0 SSD by using another device, and then reinserting the USB 3.0 SSD on the original device. A successful exploit could allow the attacker to remove container protections and perform file actions outside the namespace of the container with root privileges.
Overview
This vulnerability (CVE-2020-3396) affects Cisco IOS XE Software's IOx Guest Shell functionality when using a pluggable USB 3.0 SSD. The issue is classified as a privilege escalation vulnerability (CWE-269) that allows an attacker with physical access to the device to bypass container namespace protections. The core problem is that critical control data for the USB 3.0 SSD is not properly protected or stored on the internal boot flash, making it susceptible to tampering. By physically removing the SSD, modifying its contents using another device, and then reinserting it, an attacker could gain elevated privileges and access areas of the file system that should be restricted, potentially compromising the security of the entire system.
Remediation
To address this vulnerability, administrators should:
- Apply the appropriate security patches provided by Cisco for affected IOS XE Software versions
- Implement physical security controls to prevent unauthorized access to network devices
- Consider using alternative storage solutions if available
- Monitor for any suspicious physical access to devices
- Follow Cisco's specific guidance in the security advisory (cisco-sa-iox-usb-guestshell-WmevScDj)
- Consider disabling the IOx Guest Shell functionality if not required
- Implement proper access controls and authentication mechanisms for administrative access
- Regularly audit device configurations and security settings
References
- Cisco Security Advisory: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iox-usb-guestshell-WmevScDj
- Title: 20200924 Cisco IOS XE Software IOx Guest Shell USB SSD Namespace Protection Privilege Escalation Vulnerability
- CWE-269: Improper Privilege Management - https://cwe.mitre.org/data/definitions/269.html
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
- Finance and InsuranceFinance and Insurance
- Management of Companies & EnterprisesManagement of Companies & Enterprises
- Accommodation & Food ServicesAccommodation & Food Services
- Administrative, Support, Waste Management & Remediation ServicesAdministrative, Support, Waste Management & Remediation Services
- Agriculture, Forestry Fishing & HuntingAgriculture, Forestry Fishing & Hunting
- Arts, Entertainment & RecreationArts, Entertainment & Recreation
- ConstructionConstruction
- Educational ServicesEducational Services
- Health Care & Social AssistanceHealth Care & Social Assistance
- InformationInformation
- MiningMining
- Other Services (except Public Administration)Other Services (except Public Administration)
- Professional, Scientific, & Technical ServicesProfessional, Scientific, & Technical Services
- Public AdministrationPublic Administration
- Real Estate Rental & LeasingReal Estate Rental & Leasing
- Retail TradeRetail Trade
- Transportation & WarehousingTransportation & Warehousing
- UtilitiesUtilities
- Wholesale TradeWholesale Trade
